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Wang H, Zhao X, Wen J, Wang C, Zhang X, Ren X, Zhang J, Li H, Muhatai G, Qu L. Comparative population genomics analysis uncovers genomic footprints and genes influencing body weight trait in Chinese indigenous chicken. Poult Sci 2023; 102:103031. [PMID: 37716235 PMCID: PMC10511812 DOI: 10.1016/j.psj.2023.103031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 07/27/2023] [Accepted: 08/11/2023] [Indexed: 09/18/2023] Open
Abstract
Body weight of chicken is a typical quantitative trait, which shows phenotypic variations due to selective breeding. Despite some QTL loci have been obtained, the body weight of native chicken breeds in different geographic regions varies greatly, its genetic basis remains unresolved questions. To address this issue, we analyzed 117 Chinese indigenous chickens from 10 breeds (Huiyang Bearded, Xinhua, Hotan Black, Baicheng You, Liyang, Yunyang Da, Jining Bairi, Lindian, Beijing You, Tibetan). We applied fixation index (FST) analysis to find selected genomic regions and genes associated with body weight traits. Our study suggests that NELL1, XYLT1, and NCAPG/LCORL genes are strongly selected in the body weight trait of Chinese indigenous chicken breeds. In addition, the IL1RAPL1 gene was strongly selected in large body weight chickens, while the PCDH17 and CADM2 genes were strongly selected in small body weight chickens. This result suggests that the patterns of genetic variation of native chicken and commercial chicken, and/or distinct local chicken breeds may follow different evolutionary mechanisms.
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Affiliation(s)
- Huie Wang
- Xinjiang Production & Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science and Technology, College of Animal Science and Technology, Tarim University, Alar 843300, China
| | - Xiurong Zhao
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Junhui Wen
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Chengqian Wang
- Xinjiang Production & Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science and Technology, College of Animal Science and Technology, Tarim University, Alar 843300, China
| | - Xinye Zhang
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Xufang Ren
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Jinxin Zhang
- State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China
| | - Haiying Li
- College of Animal Science, Xinjiang Agricultural University, Urumqi 830000, China
| | - Gemingguli Muhatai
- Xinjiang Production & Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science and Technology, College of Animal Science and Technology, Tarim University, Alar 843300, China
| | - Lujiang Qu
- Xinjiang Production & Construction Corps Key Laboratory of Protection and Utilization of Biological Resources in Tarim Basin, College of Life Science and Technology, College of Animal Science and Technology, Tarim University, Alar 843300, China; State Key Laboratory of Animal Nutrition, Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Beijing 100193, China.
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2
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Taieb M, Ghannoum D, Barré L, Ouzzine M. Xylosyltransferase I mediates the synthesis of proteoglycans with long glycosaminoglycan chains and controls chondrocyte hypertrophy and collagen fibers organization of in the growth plate. Cell Death Dis 2023; 14:355. [PMID: 37296099 PMCID: PMC10256685 DOI: 10.1038/s41419-023-05875-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 04/06/2023] [Accepted: 05/31/2023] [Indexed: 06/12/2023]
Abstract
Genetic mutations in the Xylt1 gene are associated with Desbuquois dysplasia type II syndrome characterized by sever prenatal and postnatal short stature. However, the specific role of XylT-I in the growth plate is not completely understood. Here, we show that XylT-I is expressed and critical for the synthesis of proteoglycans in resting and proliferative but not in hypertrophic chondrocytes in the growth plate. We found that loss of XylT-I induces hypertrophic phenotype-like of chondrocytes associated with reduced interterritorial matrix. Mechanistically, deletion of XylT-I impairs the synthesis of long glycosaminoglycan chains leading to the formation of proteoglycans with shorter glycosaminoglycan chains. Histological and Second Harmonic Generation microscopy analysis revealed that deletion of XylT-I accelerated chondrocyte maturation and prevents chondrocytes columnar organization and arrangement in parallel of collagen fibers in the growth plate, suggesting that XylT-I controls chondrocyte maturation and matrix organization. Intriguingly, loss of XylT-I induced at embryonic stage E18.5 the migration of progenitor cells from the perichondrium next to the groove of Ranvier into the central part of epiphysis of E18.5 embryos. These cells characterized by higher expression of glycosaminoglycans exhibit circular organization then undergo hypertrophy and death creating a circular structure at the secondary ossification center location. Our study revealed an uncovered role of XylT-I in the synthesis of proteoglycans and provides evidence that the structure of glycosaminoglycan chains of proteoglycans controls chondrocyte maturation and matrix organization.
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Affiliation(s)
- Mahdia Taieb
- UMR 7365 CNRS-University of Lorraine, Biopôle, Faculty of Medicine, BP 20199, 54505, Vandoeuvre-lès-Nancy, CEDEX, France
| | - Dima Ghannoum
- UMR 7365 CNRS-University of Lorraine, Biopôle, Faculty of Medicine, BP 20199, 54505, Vandoeuvre-lès-Nancy, CEDEX, France
| | - Lydia Barré
- UMR 7365 CNRS-University of Lorraine, Biopôle, Faculty of Medicine, BP 20199, 54505, Vandoeuvre-lès-Nancy, CEDEX, France
| | - Mohamed Ouzzine
- UMR 7365 CNRS-University of Lorraine, Biopôle, Faculty of Medicine, BP 20199, 54505, Vandoeuvre-lès-Nancy, CEDEX, France.
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3
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Henke K, Farmer DT, Niu X, Kraus JM, Galloway JL, Youngstrom DW. Genetically engineered zebrafish as models of skeletal development and regeneration. Bone 2023; 167:116611. [PMID: 36395960 PMCID: PMC11080330 DOI: 10.1016/j.bone.2022.116611] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/01/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022]
Abstract
Zebrafish (Danio rerio) are aquatic vertebrates with significant homology to their terrestrial counterparts. While zebrafish have a centuries-long track record in developmental and regenerative biology, their utility has grown exponentially with the onset of modern genetics. This is exemplified in studies focused on skeletal development and repair. Herein, the numerous contributions of zebrafish to our understanding of the basic science of cartilage, bone, tendon/ligament, and other skeletal tissues are described, with a particular focus on applications to development and regeneration. We summarize the genetic strengths that have made the zebrafish a powerful model to understand skeletal biology. We also highlight the large body of existing tools and techniques available to understand skeletal development and repair in the zebrafish and introduce emerging methods that will aid in novel discoveries in skeletal biology. Finally, we review the unique contributions of zebrafish to our understanding of regeneration and highlight diverse routes of repair in different contexts of injury. We conclude that zebrafish will continue to fill a niche of increasing breadth and depth in the study of basic cellular mechanisms of skeletal biology.
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Affiliation(s)
- Katrin Henke
- Department of Orthopaedics, Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA.
| | - D'Juan T Farmer
- Department of Molecular, Cell and Developmental Biology, University of California, Los Angeles, CA 90095, USA; Department of Orthopaedic Surgery, University of California, Los Angeles, CA 90095, USA.
| | - Xubo Niu
- Center for Regenerative Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
| | - Jessica M Kraus
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.
| | - Jenna L Galloway
- Center for Regenerative Medicine, Department of Orthopaedic Surgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA.
| | - Daniel W Youngstrom
- Department of Orthopaedic Surgery, University of Connecticut Health Center, Farmington, CT 06030, USA.
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4
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Pathogenic Roles of Heparan Sulfate and Its Use as a Biomarker in Mucopolysaccharidoses. Int J Mol Sci 2022; 23:ijms231911724. [PMID: 36233030 PMCID: PMC9570396 DOI: 10.3390/ijms231911724] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/17/2022] Open
Abstract
Heparan sulfate (HS) is an essential glycosaminoglycan (GAG) as a component of proteoglycans, which are present on the cell surface and in the extracellular matrix. HS-containing proteoglycans not only function as structural constituents of the basal lamina but also play versatile roles in various physiological processes, including cell signaling and organ development. Thus, inherited mutations of genes associated with the biosynthesis or degradation of HS can cause various diseases, particularly those involving the bones and central nervous system (CNS). Mucopolysaccharidoses (MPSs) are a group of lysosomal storage disorders involving GAG accumulation throughout the body caused by a deficiency of GAG-degrading enzymes. GAGs are stored differently in different types of MPSs. Particularly, HS deposition is observed in patients with MPS types I, II, III, and VII, all which involve progressive neuropathy with multiple CNS system symptoms. While therapies are available for certain symptoms in some types of MPSs, significant unmet medical needs remain, such as neurocognitive impairment. This review presents recent knowledge on the pathophysiological roles of HS focusing on the pathogenesis of MPSs. We also discuss the possible use and significance of HS as a biomarker for disease severity and therapeutic response in MPSs.
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Schwartz NB, Domowicz MS. Roles of Chondroitin Sulfate Proteoglycans as Regulators of Skeletal Development. Front Cell Dev Biol 2022; 10:745372. [PMID: 35465334 PMCID: PMC9026158 DOI: 10.3389/fcell.2022.745372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 03/21/2022] [Indexed: 11/29/2022] Open
Abstract
The extracellular matrix (ECM) is critically important for most cellular processes including differentiation, morphogenesis, growth, survival and regeneration. The interplay between cells and the ECM often involves bidirectional signaling between ECM components and small molecules, i.e., growth factors, morphogens, hormones, etc., that regulate critical life processes. The ECM provides biochemical and contextual information by binding, storing, and releasing the bioactive signaling molecules, and/or mechanical information that signals from the cell membrane integrins through the cytoskeleton to the nucleus, thereby influencing cell phenotypes. Using these dynamic, reciprocal processes, cells can also remodel and reshape the ECM by degrading and re-assembling it, thereby sculpting their environments. In this review, we summarize the role of chondroitin sulfate proteoglycans as regulators of cell and tissue development using the skeletal growth plate model, with an emphasis on use of naturally occurring, or created mutants to decipher the role of proteoglycan components in signaling paradigms.
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Affiliation(s)
- Nancy B. Schwartz
- Department of Pediatrics, Biological Sciences Division, The University of Chicago, Chicago, IL, United States
- Department of Biochemistry and Molecular Biology, Biological Sciences Division, The University of Chicago, Chicago, IL, United States
- *Correspondence: Nancy B. Schwartz,
| | - Miriam S. Domowicz
- Department of Pediatrics, Biological Sciences Division, The University of Chicago, Chicago, IL, United States
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Guasto A, Dubail J, Aguilera-Albesa S, Paganini C, Vanhulle C, Haouari W, Gorría-Redondo N, Aznal-Sainz E, Boddaert N, Planas-Serra L, Schlüter A, Verdura E, Bruneel A, Rossi A, Huber C, Pujol A, Cormier-Daire V. Biallelic variants in SLC35B2 cause a novel chondrodysplasia with hypomyelinating leukodystrophy. Brain 2022; 145:3711-3722. [PMID: 35325049 DOI: 10.1093/brain/awac110] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Revised: 02/22/2022] [Accepted: 03/13/2022] [Indexed: 11/13/2022] Open
Abstract
Sulfated proteoglycans are essential in skeletal and brain development. Recently, pathogenic variants in genes encoding proteins involved in the proteoglycan biosynthesis have been identified in a range of chondrodysplasia associated with intellectual disability. Nevertheless, several patients remain with unidentified molecular basis. This study aimed to contribute to the deciphering of new molecular bases in patients with chondrodysplasia and neuro-developmental disease. Exome sequencing was performed to identify pathogenic variants in patients presenting with chondrodysplasia and intellectual disability. The pathogenic effects of the potentially causative variants were analyzed by functional studies. We identified homozygous variants (c.1218_1220del and c.1224_1225del) in SLC35B2 in two patients with pre- and postnatal growth retardation, scoliosis, severe motor and intellectual disabilities and hypomyelinating leukodystrophy. By functional analyses, we showed that the variants affect SLC35B2 mRNA expression and protein subcellular localization leading to a functional impairment of the protein. Consistent with those results, we detected proteoglycan sulfation impairment in SLC35B2 patient fibroblasts and serum. Our data support that SLC35B2 functional impairment causes a novel syndromic chondrodysplasia with hypomyelinating leukodystrophy, most likely through a proteoglycan sulfation defect. This is the first time that SLC35B2 variants are associated with bone and brain development in human.
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Affiliation(s)
- Alessandra Guasto
- Paris Cité University, INSERM UMR1163, Imagine Institute, 75015 Paris, France
| | - Johanne Dubail
- Paris Cité University, INSERM UMR1163, Imagine Institute, 75015 Paris, France
| | - Sergio Aguilera-Albesa
- Pediatric Neurology Unit, Department of Pediatrics, Complejo Hospitalario de Navarra, Navarrabiomed, Pamplona, Spain.,Children's Medically Complex Diseases Unit, Department of Pediatrics, Complejo Hospitalario de Navarra, Pamplona, Spain
| | - Chiara Paganini
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Pavia, Italy
| | - Catherine Vanhulle
- Service de Neuropédiatrie, pavillon Martainville, Hôpital Charles Nicolle, 76031, Rouen, France
| | - Walid Haouari
- INSERM UMR1193, Paris-Saclay University, F-92220 Châtenay-Malabry, France
| | - Nerea Gorría-Redondo
- Pediatric Neurology Unit, Department of Pediatrics, Complejo Hospitalario de Navarra, Navarrabiomed, Pamplona, Spain
| | - Elena Aznal-Sainz
- Children's Medically Complex Diseases Unit, Department of Pediatrics, Complejo Hospitalario de Navarra, Pamplona, Spain
| | - Nathalie Boddaert
- Service d'Imagerie pédiatrique, AP-HP, Hôpital Necker-Enfants malades, F-75015 Paris, France
| | - Laura Planas-Serra
- Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, 08908, Barcelona, Catalonia, Spain.,Centre for Biomedical Research in Network on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Agatha Schlüter
- Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, 08908, Barcelona, Catalonia, Spain.,Centre for Biomedical Research in Network on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Edgard Verdura
- Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, 08908, Barcelona, Catalonia, Spain.,Centre for Biomedical Research in Network on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029, Madrid, Spain
| | - Arnaud Bruneel
- INSERM UMR1193, Paris-Saclay University, F-92220 Châtenay-Malabry, France.,AP-HP, Biochimie métabolique et cellulaire, Hôpital Bichat, F-75018, Paris, France
| | - Antonio Rossi
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Pavia, Italy
| | - Céline Huber
- Paris Cité University, INSERM UMR1163, Imagine Institute, 75015 Paris, France
| | - Aurora Pujol
- Neurometabolic Diseases Laboratory, Bellvitge Biomedical Research Institute (IDIBELL), L'Hospitalet de Llobregat, 08908, Barcelona, Catalonia, Spain.,Centre for Biomedical Research in Network on Rare Diseases (CIBERER), Instituto de Salud Carlos III, 28029, Madrid, Spain.,Catalan Institution of Research and Advanced Studies (ICREA), Barcelona, Catalonia, Spain
| | - Valérie Cormier-Daire
- Paris Cité University, INSERM UMR1163, Imagine Institute, 75015 Paris, France.,Service de Génétique clinique, Centre de référence pour les maladies osseuses constitutionnelles, AP-HP, Hôpital Necker-Enfants malades, F-75015 Paris, France
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7
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Rajabi F, Bereshneh AH, Ramezanzadeh M, Garshasbi M. Novel compound heterozygous variants in XYLT1 gene caused Desbuquois dysplasia type 2 in an aborted fetus: a case report. BMC Pediatr 2022; 22:63. [PMID: 35081921 PMCID: PMC8790879 DOI: 10.1186/s12887-022-03132-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2021] [Accepted: 01/15/2022] [Indexed: 11/16/2022] Open
Abstract
Background Desbuquois dysplasia type 2 (DBQD2) is an infrequent dysplasia with a wide range of symptoms, including facial deformities, growth retardation and short long bones. It is an autosomal recessive disorder caused by mutations in the XYLT1 gene that encodes xylosyltransferase-1. Case presentation We studied an aborted fetus from Iranian non-consanguineous parents who was therapeutically aborted at 19 weeks of gestation. Ultrasound examinations at 18 weeks of gestation revealed growth retardation in her long bones and some facial problems. Whole-exome sequencing was performed on the aborted fetus which revealed compound heterozygous XYLT1 mutations: c.742G>A; p.(Glu248Lys) and c.1537 C>A; p.(Leu513Met). Sanger sequencing and segregation analysis confirmed the compound heterozygosity of these variants in XYLT1. Conclusion The c.1537 C>A; p.(Leu513Met) variant has not been reported in any databases so far and therefore is novel. This is the third compound heterozygote report in XYLT1 and further supports the high heterogeneity of this disease. Supplementary Information The online version contains supplementary material available at 10.1186/s12887-022-03132-5.
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Affiliation(s)
- Fatemeh Rajabi
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ali Hosseini Bereshneh
- Prenatal Diagnosis and Genetic Research Center, Dastgheib Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mahboubeh Ramezanzadeh
- Department of Genetics and Molecular Medicine, Faculty of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran
| | - Masoud Garshasbi
- Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
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8
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Hellicar J, Stevenson NL, Stephens DJ, Lowe M. Supply chain logistics - the role of the Golgi complex in extracellular matrix production and maintenance. J Cell Sci 2022; 135:273996. [PMID: 35023559 PMCID: PMC8767278 DOI: 10.1242/jcs.258879] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The biomechanical and biochemical properties of connective tissues are determined by the composition and quality of their extracellular matrix. This, in turn, is highly dependent on the function and organisation of the secretory pathway. The Golgi complex plays a vital role in directing matrix output by co-ordinating the post-translational modification and proteolytic processing of matrix components prior to their secretion. These modifications have broad impacts on the secretion and subsequent assembly of matrix components, as well as their function in the extracellular environment. In this Review, we highlight the role of the Golgi in the formation of an adaptable, healthy matrix, with a focus on proteoglycan and procollagen secretion as example cargoes. We then discuss the impact of Golgi dysfunction on connective tissue in the context of human disease and ageing.
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Affiliation(s)
- John Hellicar
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK.,Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology and Research (A*STAR), 61 Biopolis Drive, Proteos, Singapore, 138673
| | - Nicola L Stevenson
- Cell Biology Laboratories, School of Biochemistry, Faculty of Life Sciences, University Walk, University of Bristol, Bristol, BS8 1TD, UK
| | - David J Stephens
- Cell Biology Laboratories, School of Biochemistry, Faculty of Life Sciences, University Walk, University of Bristol, Bristol, BS8 1TD, UK
| | - Martin Lowe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
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Mizumoto S, Yamada S. Congenital Disorders of Deficiency in Glycosaminoglycan Biosynthesis. Front Genet 2021; 12:717535. [PMID: 34539746 PMCID: PMC8446454 DOI: 10.3389/fgene.2021.717535] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 08/12/2021] [Indexed: 12/04/2022] Open
Abstract
Glycosaminoglycans (GAGs) including chondroitin sulfate, dermatan sulfate, and heparan sulfate are covalently attached to specific core proteins to form proteoglycans, which are distributed at the cell surface as well as in the extracellular matrix. Proteoglycans and GAGs have been demonstrated to exhibit a variety of physiological functions such as construction of the extracellular matrix, tissue development, and cell signaling through interactions with extracellular matrix components, morphogens, cytokines, and growth factors. Not only connective tissue disorders including skeletal dysplasia, chondrodysplasia, multiple exostoses, and Ehlers-Danlos syndrome, but also heart and kidney defects, immune deficiencies, and neurological abnormalities have been shown to be caused by defects in GAGs as well as core proteins of proteoglycans. These findings indicate that GAGs and proteoglycans are essential for human development in major organs. The glycobiological aspects of congenital disorders caused by defects in GAG-biosynthetic enzymes including specific glysocyltransferases, epimerases, and sulfotransferases, in addition to core proteins of proteoglycans will be comprehensively discussed based on the literature to date.
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Affiliation(s)
- Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Shuhei Yamada
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan
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10
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Rios JJ, Denton K, Russell J, Kozlitina J, Ferreira CR, Lewanda AF, Mayfield JE, Moresco E, Ludwig S, Tang M, Li X, Lyon S, Khanshour A, Paria N, Khalid A, Li Y, Xie X, Feng JQ, Xu Q, Lu Y, Hammer RE, Wise CA, Beutler B. Germline Saturation Mutagenesis Induces Skeletal Phenotypes in Mice. J Bone Miner Res 2021; 36:1548-1565. [PMID: 33905568 PMCID: PMC8862308 DOI: 10.1002/jbmr.4323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 04/07/2021] [Accepted: 04/21/2021] [Indexed: 12/28/2022]
Abstract
Proper embryonic and postnatal skeletal development require coordination of myriad complex molecular mechanisms. Disruption of these processes, through genetic mutation, contributes to variation in skeletal development. We developed a high-throughput N-ethyl-N-nitrosourea (ENU)-induced saturation mutagenesis skeletal screening approach in mice to identify genes required for proper skeletal development. Here, we report initial results from live-animal X-ray and dual-energy X-ray absorptiometry (DXA) imaging of 27,607 G3 mice from 806 pedigrees, testing the effects of 32,198 coding/splicing mutations in 13,020 genes. A total of 39.7% of all autosomal genes were severely damaged or destroyed by mutations tested twice or more in the homozygous state. Results from our study demonstrate the feasibility of in vivo mutagenesis to identify mouse models of skeletal disease. Furthermore, our study demonstrates how ENU mutagenesis provides opportunities to create and characterize putative hypomorphic mutations in developmentally essential genes. Finally, we present a viable mouse model and case report of recessive skeletal disease caused by mutations in FAM20B. Results from this study, including engineered mouse models, are made publicly available via the online Mutagenetix database. © 2021 American Society for Bone and Mineral Research (ASBMR).
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Affiliation(s)
- Jonathan J Rios
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA.,Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA.,McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, TX, USA.,Simmons Comprehensive Cancer Center, UT Southwestern Medical Center, Dallas, TX, USA
| | - Kristin Denton
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Jamie Russell
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Julia Kozlitina
- McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA
| | - Carlos R Ferreira
- Skeletal Genomics Unit, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Amy F Lewanda
- Rare Disease Institute, Children's National Hospital, Washington, DC, USA
| | - Joshua E Mayfield
- Department of Pharmacology, University of California, San Diego, CA, USA
| | - Eva Moresco
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Sara Ludwig
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Miao Tang
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Xiaohong Li
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Stephen Lyon
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
| | - Anas Khanshour
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Nandina Paria
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Aysha Khalid
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Yang Li
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA
| | - Xudong Xie
- Department of Restorative Sciences, School of Dentistry, Texas A&M University, Dallas, TX, USA
| | - Jian Q Feng
- Department of Restorative Sciences, School of Dentistry, Texas A&M University, Dallas, TX, USA
| | - Qian Xu
- Department of Restorative Sciences, School of Dentistry, Texas A&M University, Dallas, TX, USA
| | - Yongbo Lu
- Department of Restorative Sciences, School of Dentistry, Texas A&M University, Dallas, TX, USA
| | - Robert E Hammer
- Department of Biochemistry, UT Southwestern Medical Center, Dallas, TX, USA
| | - Carol A Wise
- Center for Pediatric Bone Biology and Translational Research, Scottish Rite for Children, Dallas, TX, USA.,Department of Pediatrics, UT Southwestern Medical Center, Dallas, TX, USA.,McDermott Center for Human Growth and Development, UT Southwestern Medical Center, Dallas, TX, USA.,Department of Orthopaedic Surgery, UT Southwestern Medical Center, Dallas, TX, USA
| | - Bruce Beutler
- Center for Genetics of Host Defense, UT Southwestern Medical Center, Dallas, TX, USA
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Kai Y, Yoneyama H, Yoshikawa M, Kimura H, Muro S. Chondroitin sulfate in tissue remodeling: Therapeutic implications for pulmonary fibrosis. Respir Investig 2021; 59:576-588. [PMID: 34176780 DOI: 10.1016/j.resinv.2021.05.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 05/14/2021] [Accepted: 05/21/2021] [Indexed: 10/21/2022]
Abstract
Fibrosis is characterized by the deposition of extracellular matrix (ECM) proteins, while idiopathic pulmonary fibrosis (IPF) is a chronic respiratory disease characterized by dysregulated tissue repair and remodeling. Anti-inflammatory drugs, such as corticosteroids and immunosuppressants, and antifibrotic drugs, like pirfenidone and nintedanib, are used in IPF therapy. However, their limited effects suggest that single mediators are inadequate to control IPF. Therefore, therapies targeting the multifactorial cascades that regulate tissue remodeling in fibrosis could provide alternate solutions. ECM molecules have been shown to modulate various biological functions beyond tissue structure support and thus, could be developed into novel therapeutic targets for modulating tissue remodeling. Among ECM molecules, glycosaminoglycans (GAG) are linear polysaccharides consisting of repeated disaccharides, which regulate cell-matrix interactions. Chondroitin sulfate (CS), one of the major GAGs, binds to multifactorial mediators in the ECM and reportedly participates in tissue remodeling in various diseases; however, to date, its biological functions have drawn considerably less attention than other GAGs, like heparan sulfate. In the present review, we discuss the involvement and regulation of CS in tissue remodeling and pulmonary fibrotic diseases, its role in pulmonary fibrosis, and the therapeutic approaches targeting CS.
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Affiliation(s)
- Yoshiro Kai
- Department of Respiratory Medicine, Nara Medical University, 840 Shijo-cho, Kashihara-city, Nara, 634-8522, Japan; Department of Respiratory Medicine, Minami-Nara General Medical Center, 8-1 Fukugami, Oyodo-cho, Yoshino-gun, Nara, 638-8551, Japan.
| | - Hiroyuki Yoneyama
- TME Therapeutics Inc., 2-16-1 Higashi-shinbashi, Minato-ku, Tokyo, 105-0021, Japan.
| | - Masanori Yoshikawa
- Department of Respiratory Medicine, Nara Medical University, 840 Shijo-cho, Kashihara-city, Nara, 634-8522, Japan.
| | - Hiroshi Kimura
- Respiratory Disease Center, Fukujuji Hospital, Japan Anti-Tuberculosis Association, 3-1-24 Matsuyama, Kiyose-city, Tokyo, 204-8522, Japan.
| | - Shigeo Muro
- Department of Respiratory Medicine, Nara Medical University, 840 Shijo-cho, Kashihara-city, Nara, 634-8522, Japan.
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12
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Dubail J, Cormier-Daire V. Chondrodysplasias With Multiple Dislocations Caused by Defects in Glycosaminoglycan Synthesis. Front Genet 2021; 12:642097. [PMID: 34220933 PMCID: PMC8242584 DOI: 10.3389/fgene.2021.642097] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 05/04/2021] [Indexed: 11/13/2022] Open
Abstract
Chondrodysplasias with multiple dislocations form a group of severe disorders characterized by joint laxity and multiple dislocations, severe short stature of pre- and post-natal onset, hand anomalies, and/or vertebral anomalies. The majority of chondrodysplasias with multiple dislocations have been associated with mutations in genes encoding glycosyltransferases, sulfotransferases, and transporters implicated in the synthesis or sulfation of glycosaminoglycans, long and unbranched polysaccharides composed of repeated disaccharide bond to protein core of proteoglycan. Glycosaminoglycan biosynthesis is a tightly regulated process that occurs mainly in the Golgi and that requires the coordinated action of numerous enzymes and transporters as well as an adequate Golgi environment. Any disturbances of this chain of reactions will lead to the incapacity of a cell to construct correct glycanic chains. This review focuses on genetic and glycobiological studies of chondrodysplasias with multiple dislocations associated with glycosaminoglycan biosynthesis defects and related animal models. Strong comprehension of the molecular mechanisms leading to those disorders, mostly through extensive phenotypic analyses of in vitro and/or in vivo models, is essential for the development of novel biomarkers for clinical screenings and innovative therapeutics for these diseases.
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Affiliation(s)
- Johanne Dubail
- Université de Paris, INSERM UMR 1163, Institut Imagine, Paris, France
| | - Valérie Cormier-Daire
- Université de Paris, INSERM UMR 1163, Institut Imagine, Paris, France.,Service de Génétique Clinique, Centre de Référence Pour Les Maladies Osseuses Constitutionnelles, AP-HP, Hôpital Necker-Enfants Malades, Paris, France
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13
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Advances in repeat expansion diseases and a new concept of repeat motif-phenotype correlation. Curr Opin Genet Dev 2020; 65:176-185. [PMID: 32777681 DOI: 10.1016/j.gde.2020.05.029] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 05/22/2020] [Indexed: 12/19/2022]
Abstract
Recently repeat expansions have been found in more than 10 diseases in the past two years. Because the same repeat motifs are found in similar disease (as exemplified by benign adult familial myoclonic epilepsy) or in diseases with overlapping phenotype (as exemplified by fragile X tremor/ataxia syndrome, neuronal intranuclear inclusion disease, oculopharyngeal myopathy with leukoencephalopathy, and oculopharyngodistal myopathy), we propose a new concept of 'repeat motif-phenotype correlation', which argue for toxic gain-of-function mechanism caused by expanded repeats, rather than altered functions of genes harboring expanded repeats. The concept is expected to help identify repeat expansions taking the similar or overlapping clinical presentations as the clues. Although repeat expansions have been identified predominantly in autosomal dominant diseases, recent progresses have demonstrated that they are also observed in autosomal recessive diseases. Furthermore, repeat expansions are not infrequently observed in patients without family histories, which urges us to pay attention to sporadic diseases. We should expand our views toward repeat expansion diseases to accelerate discovery of diseases caused by repeat expansions, better understanding the disease mechanisms, and development of therapeutic measures.
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14
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Liu H, Barnes J, Pedrosa E, Herman NS, Salas F, Wang P, Zheng D, Lachman HM. Transcriptome analysis of neural progenitor cells derived from Lowe syndrome induced pluripotent stem cells: identification of candidate genes for the neurodevelopmental and eye manifestations. J Neurodev Disord 2020; 12:14. [PMID: 32393163 PMCID: PMC7212686 DOI: 10.1186/s11689-020-09317-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 04/28/2020] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Lowe syndrome (LS) is caused by loss-of-function mutations in the X-linked gene OCRL, which codes for an inositol polyphosphate 5-phosphatase that plays a key role in endosome recycling, clathrin-coated pit formation, and actin polymerization. It is characterized by congenital cataracts, intellectual and developmental disability, and renal proximal tubular dysfunction. Patients are also at high risk for developing glaucoma and seizures. We recently developed induced pluripotent stem cell (iPSC) lines from three patients with LS who have hypomorphic variants affecting the 3' end of the gene, and their neurotypical brothers to serve as controls. METHODS In this study, we used RNA sequencing (RNA-seq) to obtain transcriptome profiles in LS and control neural progenitor cells (NPCs). RESULTS In a comparison of the patient and control NPCs (n = 3), we found 16 differentially expressed genes (DEGs) at the multiple test adjusted p value (padj) < 0.1, with nine at padj < 0.05. Using nominal p value < 0.05, 319 DEGs were detected. The relatively small number of DEGs could be due to the fact that OCRL is not a transcription factor per se, although it could have secondary effects on gene expression through several different mechanisms. Although the number of DEGs passing multiple test correction was small, those that were found are quite consistent with some of the known molecular effects of OCRL protein, and the clinical manifestations of LS. Furthermore, using gene set enrichment analysis (GSEA), we found that genes increased expression in the patient NPCs showed enrichments of several gene ontology (GO) terms (false discovery rate < 0.25): telencephalon development, pallium development, NPC proliferation, and cortex development, which are consistent with a condition characterized by intellectual disabilities and psychiatric manifestations. In addition, a significant enrichment among the nominal DEGs for genes implicated in autism spectrum disorder (ASD) was found (e.g., AFF2, DNER, DPP6, DPP10, RELN, CACNA1C), as well as several that are strong candidate genes for the development of eye problems found in LS, including glaucoma. The most notable example is EFEMP1, a well-known candidate gene for glaucoma and other eye pathologies. CONCLUSION Overall, the RNA-seq findings present several candidate genes that could help explain the underlying basis for the neurodevelopmental and eye problems seen in boys with LS.
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Affiliation(s)
- Hequn Liu
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Jesse Barnes
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Erika Pedrosa
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Nathaniel S. Herman
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Franklin Salas
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Ping Wang
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Deyou Zheng
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA
- Dominick P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, USA
- Department of Neurology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Herbert M. Lachman
- Department of Genetics, Albert Einstein College of Medicine, Bronx, New York, USA
- Department of Psychiatry and Behavioral Sciences, Albert Einstein College of Medicine, Bronx, New York, USA
- Dominick P Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, New York, USA
- Department of Medicine, Albert Einstein College of Medicine, Bronx, New York, USA
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15
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Mizumoto S, Janecke AR, Sadeghpour A, Povysil G, McDonald MT, Unger S, Greber‐Platzer S, Deak KL, Katsanis N, Superti‐Furga A, Sugahara K, Davis EE, Yamada S, Vodopiutz J. CSGALNACT1-congenital disorder of glycosylation: A mild skeletal dysplasia with advanced bone age. Hum Mutat 2020; 41:655-667. [PMID: 31705726 PMCID: PMC7027858 DOI: 10.1002/humu.23952] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2019] [Revised: 10/30/2019] [Accepted: 11/07/2019] [Indexed: 01/22/2023]
Abstract
Congenital disorders of glycosylation (CDGs) comprise a large number of inherited metabolic defects that affect the biosynthesis and attachment of glycans. CDGs manifest as a broad spectrum of disease, most often including neurodevelopmental and skeletal abnormalities and skin laxity. Two patients with biallelic CSGALNACT1 variants and a mild skeletal dysplasia have been described previously. We investigated two unrelated patients presenting with short stature with advanced bone age, facial dysmorphism, and mild language delay, in whom trio-exome sequencing identified novel biallelic CSGALNACT1 variants: compound heterozygosity for c.1294G>T (p.Asp432Tyr) and the deletion of exon 4 that includes the start codon in one patient, and homozygosity for c.791A>G (p.Asn264Ser) in the other patient. CSGALNACT1 encodes CSGalNAcT-1, a key enzyme in the biosynthesis of sulfated glycosaminoglycans chondroitin and dermatan sulfate. Biochemical studies demonstrated significantly reduced CSGalNAcT-1 activity of the novel missense variants, as reported previously for the p.Pro384Arg variant. Altered levels of chondroitin, dermatan, and heparan sulfate moieties were observed in patients' fibroblasts compared to controls. Our data indicate that biallelic loss-of-function mutations in CSGALNACT1 disturb glycosaminoglycan synthesis and cause a mild skeletal dysplasia with advanced bone age, CSGALNACT1-CDG.
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Affiliation(s)
- Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of PharmacyMeijo UniversityNagoyaJapan
- Department of Women's and Children's Health, Clinical Genetics Group, Dunedin School of MedicineUniversity of OtagoDunedinNew Zealand
| | - Andreas R. Janecke
- Department of Pediatrics IMedical University of InnsbruckInnsbruckAustria
- Division of Human GeneticsMedical University of InnsbruckInnsbruckAustria
| | - Azita Sadeghpour
- Center for Human Disease ModelingDuke University Medical CenterDurhamNorth Carolina
| | - Gundula Povysil
- Institute of BioinformaticsJohannes Kepler UniversityLinzAustria
| | - Marie T. McDonald
- Department of Pediatrics, Division of Medical GeneticsDuke University Medical CenterDurhamNorth Carolina
| | - Sheila Unger
- Department of Medical Genetics, Centre Hospitalier Universitaire VaudoisUniversity of LausanneLausanneSwitzerland
| | - Susanne Greber‐Platzer
- Department of Pediatrics and Adolescent Medicine, Comprehensive Center for PediatricsMedical University of ViennaViennaAustria
| | - Kristen L. Deak
- Department of PathologyDuke University Medical CenterDurhamNorth Carolina
| | - Nicholas Katsanis
- Center for Human Disease ModelingDuke University Medical CenterDurhamNorth Carolina
- Advanced Center for Translational and Genetic Medicine (ACT‐GeM), Stanley Manne Children's Research InstituteAnn & Robert H. Lurie Children's Hospital of ChicagoChicagoIllinois
- Department of Pediatrics, Feinberg School of MedicineNorthwestern UniversityChicagoIllinois
| | - Andrea Superti‐Furga
- Department of Pediatrics, Centre Hospitalier Universitaire VaudoisUniversity of LausanneLausanneSwitzerland
| | - Kazuyuki Sugahara
- Department of Pathobiochemistry, Faculty of PharmacyMeijo UniversityNagoyaJapan
| | - Erica E. Davis
- Center for Human Disease ModelingDuke University Medical CenterDurhamNorth Carolina
- Advanced Center for Translational and Genetic Medicine (ACT‐GeM), Stanley Manne Children's Research InstituteAnn & Robert H. Lurie Children's Hospital of ChicagoChicagoIllinois
- Department of Pediatrics, Feinberg School of MedicineNorthwestern UniversityChicagoIllinois
| | - Shuhei Yamada
- Department of Pathobiochemistry, Faculty of PharmacyMeijo UniversityNagoyaJapan
| | - Julia Vodopiutz
- Department of Pediatrics and Adolescent Medicine, Comprehensive Center for PediatricsMedical University of ViennaViennaAustria
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16
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Fischer B, Ly TD, Schmidt V, Hendig D, Kuhn J, Knabbe C, Faust I. Xylosyltransferase-deficient human HEK293 cells show a strongly reduced proliferation capacity and viability. Biochem Biophys Res Commun 2020; 521:507-513. [PMID: 31677793 DOI: 10.1016/j.bbrc.2019.10.148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Accepted: 10/22/2019] [Indexed: 01/08/2023]
Abstract
Human xylosyltransferases-I and -II (XT-I and XT-II) catalyze the initial and rate-limiting step in proteoglycan (PG)-biosynthesis. Because PG are major components of the extracellular matrix (ECM), an alternated XT expression is associated with the manifestation of ECM-related diseases. While Drosophila melanogaster and Caenorhabditis elegans only harbor one XT-isoform, all higher organisms contain two isoforms, which are expressed in a tissue-specific manner. The reason for the appearance of two isoenzymes remains unexplained and remarkable, as all other enzymes involved in the synthesis of the tetrasaccharid linker, which connects the PG core protein with attached glycosaminoglycans, only show one isoform. In human, mutations in the XYLT genes cause diseases affecting the homeostasis of the ECM, such as skeletal dysplasias. We investigated for the first time whether already XT-I-deficient human embryonic kidney (HEK293) cells can compensate for decreased expression levels of both XT-isoforms. A siRNA-mediated XYLT2 mRNA knockdown led to reduced cellular proliferation rates and a partially increased cellular senescence of treated HEK293 cells. These results were verified by conducting a stable CRISPR/Cas9-mediated XYLT2 knockout, which revealed that only cells expressing at least partially functional XT-II proteins remain proliferative. Our study, therefore, shows for the first time that cells lacking both XT-isoforms are not viable and clearly indicates the importance of the XT concerning the cellular metabolism.
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Affiliation(s)
- Bastian Fischer
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany.
| | - Thanh-Diep Ly
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Vanessa Schmidt
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Doris Hendig
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Joachim Kuhn
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
| | - Isabel Faust
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstrasse 11, 32545, Bad Oeynhausen, Germany
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17
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Caraffi SG, Maini I, Ivanovski I, Pollazzon M, Giangiobbe S, Valli M, Rossi A, Sassi S, Faccioli S, Rocco MD, Magnani C, Campos-Xavier B, Unger S, Superti-Furga A, Garavelli L. Severe Peripheral Joint Laxity is a Distinctive Clinical Feature of Spondylodysplastic-Ehlers-Danlos Syndrome (EDS)- B4GALT7 and Spondylodysplastic-EDS- B3GALT6. Genes (Basel) 2019; 10:genes10100799. [PMID: 31614862 PMCID: PMC6826576 DOI: 10.3390/genes10100799] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 09/25/2019] [Accepted: 10/11/2019] [Indexed: 12/13/2022] Open
Abstract
Variations in genes encoding for the enzymes responsible for synthesizing the linker region of proteoglycans may result in recessive conditions known as "linkeropathies". The two phenotypes related to mutations in genes B4GALT7 and B3GALT6 (encoding for galactosyltransferase I and II respectively) are similar, characterized by short stature, hypotonia, joint hypermobility, skeletal features and a suggestive face with prominent forehead, thin soft tissue and prominent eyes. The most outstanding feature of these disorders is the combination of severe connective tissue involvement, often manifesting in newborns and infants, and skeletal dysplasia that becomes apparent during childhood. Here, we intend to more accurately define some of the clinical features of B4GALT7 and B3GALT6-related conditions and underline the extreme hypermobility of distal joints and the soft, doughy skin on the hands and feet as features that may be useful as the first clues for a correct diagnosis.
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Affiliation(s)
- Stefano Giuseppe Caraffi
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
| | - Ilenia Maini
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
- Child Neuropsychiatry Unit, Azienda USL of Parma, 43125 Parma, Italy.
| | - Ivan Ivanovski
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
- Department of Surgical, Medical, Dental and Morphological Sciences with interest in Transplant, Oncology and Regenerative Medicine, University of Modena and Reggio Emilia, 42121 Reggio Emilia, Italy.
| | - Marzia Pollazzon
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
| | - Sara Giangiobbe
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
| | - Maurizia Valli
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, 27100 Pavia, Italy.
| | - Antonio Rossi
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, 27100 Pavia, Italy.
| | - Silvia Sassi
- Rehabilitation Pediatric Unit, Azienda USL-IRCCS of Reggio Emilia, Reggio Emilia, 42122 Reggio Emilia, Italy.
| | - Silvia Faccioli
- Rehabilitation Pediatric Unit, Azienda USL-IRCCS of Reggio Emilia, Reggio Emilia, 42122 Reggio Emilia, Italy.
| | - Maja Di Rocco
- Department of Pediatrics, Unit of Rare Diseases, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy.
| | - Cinzia Magnani
- Neonatology and Neonatal Intensive Care Unit, Maternal and Child Department, University of Parma, 43121 Parma, Italy.
| | - Belinda Campos-Xavier
- Division of Genetic Medicine, Centre Hospitalier Universitaire Vaudois (CHUV), University of Lausanne, 1011 Lausanne, Switzerland.
| | - Sheila Unger
- Division of Genetic Medicine, Centre Hospitalier Universitaire Vaudois (CHUV), University of Lausanne, 1011 Lausanne, Switzerland.
| | - Andrea Superti-Furga
- Division of Genetic Medicine, Centre Hospitalier Universitaire Vaudois (CHUV), University of Lausanne, 1011 Lausanne, Switzerland.
| | - Livia Garavelli
- Medical Genetics Unit, Maternal and Child Health Department, Azienda USL-IRCCS of Reggio Emilia, 42122 Reggio Emilia, Italy.
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18
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Further Defining the Phenotypic Spectrum of B3GAT3 Mutations and Literature Review on Linkeropathy Syndromes. Genes (Basel) 2019; 10:genes10090631. [PMID: 31438591 PMCID: PMC6770791 DOI: 10.3390/genes10090631] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 08/09/2019] [Accepted: 08/19/2019] [Indexed: 11/29/2022] Open
Abstract
The term linkeropathies (LKs) refers to a group of rare heritable connective tissue disorders, characterized by a variable degree of short stature, skeletal dysplasia, joint laxity, cutaneous anomalies, dysmorphism, heart malformation, and developmental delay. The LK genes encode for enzymes that add glycosaminoglycan chains onto proteoglycans via a common tetrasaccharide linker region. Biallelic variants in XYLT1 and XYLT2, encoding xylosyltransferases, are associated with Desbuquois dysplasia type 2 and spondylo-ocular syndrome, respectively. Defects in B4GALT7 and B3GALT6, encoding galactosyltransferases, lead to spondylodysplastic Ehlers-Danlos syndrome (spEDS). Mutations in B3GAT3, encoding a glucuronyltransferase, were described in 25 patients from 12 families with variable phenotypes resembling Larsen, Antley-Bixler, Shprintzen-Goldberg, and Geroderma osteodysplastica syndromes. Herein, we report on a 13-year-old girl with a clinical presentation suggestive of spEDS, according to the 2017 EDS nosology, in whom compound heterozygosity for two B3GAT3 likely pathogenic variants was identified. We review the spectrum of B3GAT3-related disorders and provide a comparison of all LK patients reported up to now, highlighting that LKs are a phenotypic continuum bridging EDS and skeletal disorders, hence offering future nosologic perspectives.
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19
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Paganini C, Costantini R, Superti-Furga A, Rossi A. Bone and connective tissue disorders caused by defects in glycosaminoglycan biosynthesis: a panoramic view. FEBS J 2019; 286:3008-3032. [PMID: 31286677 DOI: 10.1111/febs.14984] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2019] [Revised: 05/22/2019] [Accepted: 07/04/2019] [Indexed: 02/06/2023]
Abstract
Glycosaminoglycans (GAGs) are a heterogeneous family of linear polysaccharides that constitute the carbohydrate moiety covalently attached to the protein core of proteoglycans, macromolecules present on the cell surface and in the extracellular matrix. Several genetic disorders of bone and connective tissue are caused by mutations in genes encoding for glycosyltransferases, sulfotransferases and transporters that are responsible for the synthesis of sulfated GAGs. Phenotypically, these disorders all reflect alterations in crucial biological functions of GAGs in the development, growth and homoeostasis of cartilage and bone. To date, up to 27 different skeletal phenotypes have been linked to mutations in 23 genes encoding for proteins involved in GAG biosynthesis. This review focuses on recent genetic, molecular and biochemical studies of bone and connective tissue disorders caused by GAG synthesis defects. These insights and future research in the field will provide a deeper understanding of the molecular pathogenesis of these disorders and will pave the way for developing common therapeutic strategies that might be targeted to a range of individual phenotypes.
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Affiliation(s)
- Chiara Paganini
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Italy
| | - Rossella Costantini
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Italy
| | - Andrea Superti-Furga
- Division of Genetic Medicine, Lausanne University Hospital, University of Lausanne, Switzerland
| | - Antonio Rossi
- Department of Molecular Medicine, Unit of Biochemistry, University of Pavia, Italy
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20
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Colman M, Van Damme T, Steichen-Gersdorf E, Laccone F, Nampoothiri S, Syx D, Guillemyn B, Symoens S, Malfait F. The clinical and mutational spectrum of B3GAT3 linkeropathy: two case reports and literature review. Orphanet J Rare Dis 2019; 14:138. [PMID: 31196143 PMCID: PMC6567438 DOI: 10.1186/s13023-019-1110-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Accepted: 06/04/2019] [Indexed: 01/07/2023] Open
Abstract
Background Proteoglycans are large and structurally complex macromolecules which can be found in abundancy in the extracellular matrix and on the surface of all animal cells. Mutations in the genes encoding the enzymes responsible for the formation of the tetrasaccharide linker region between the proteoglycan core protein and the glycosaminoglycan side chains lead to a spectrum of severe and overlapping autosomal recessive connective tissue disorders, collectively coined the ‘glycosaminoglycan linkeropathies’. Results We report the clinical findings of two novel patients with a complex linkeropathy due to biallelic mutations in B3GAT3, the gene that encodes glucuronosyltransferase I, which catalyzes the addition of the ultimate saccharide to the linker region. We identified a previously reported c.667G > A missense mutation and an unreported homozygous c.416C > T missense mutation. We also performed a genotype and phenotype-oriented literature overview of all hitherto reported patients harbouring B3GAT3 mutations. A total of 23 patients from 10 families harbouring bi-allelic mutations and one patient with a heterozygeous splice-site mutation in B3GAT3 have been reported. They all display a complex phenotype characterized by consistent presence of skeletal dysplasia (including short stature, kyphosis, scoliosis and deformity of the long bones), facial dysmorphology, and spatulate distal phalanges. More variably present are cardiac defects, joint hypermobility, joint dislocations/contractures and fractures. Seven different B3GAT3 mutations have been reported, and although the number of patients is still limited, some phenotype-genotype correlations start to emerge. The more severe phenotypes seem to have mutations located in the substrate acceptor subdomain of the catalytic domain of the glucuronosyltransferase I protein while more mildly affected phenotypes seem to have mutations in the NTP-sugar donor substrate binding subdomain. Conclusions Loss-of-function mutations in B3GAT3 are associated with a complex connective tissue phenotype characterized by disproportionate short stature, skeletal dysplasia, facial dysmorphism, spatulate distal phalanges and -to a lesser extent- joint contractures, joint hypermobility with dislocations, cardiac defects and bone fragility. Based on the limited number of reported patients, some genotype-phenotype correlations start to emerge.
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Affiliation(s)
- Marlies Colman
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium
| | - Tim Van Damme
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium
| | | | | | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences & Research Centre, Kerala, India
| | - Delfien Syx
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium
| | - Brecht Guillemyn
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium
| | - Sofie Symoens
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium
| | - Fransiska Malfait
- Center for Medical Genetics, Ghent University and Ghent University Hospital, 0K5, Corneel Heymanslaan 10, B-9000, Ghent, Belgium.
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21
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Van Damme T, Pang X, Guillemyn B, Gulberti S, Syx D, De Rycke R, Kaye O, de Die-Smulders CEM, Pfundt R, Kariminejad A, Nampoothiri S, Pierquin G, Bulk S, Larson AA, Chatfield KC, Simon M, Legrand A, Gerard M, Symoens S, Fournel-Gigleux S, Malfait F. Biallelic B3GALT6 mutations cause spondylodysplastic Ehlers-Danlos syndrome. Hum Mol Genet 2019; 27:3475-3487. [PMID: 29931299 DOI: 10.1093/hmg/ddy234] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 06/14/2018] [Indexed: 11/15/2022] Open
Abstract
Proteoglycans are among the most abundant and structurally complex biomacromolecules and play critical roles in connective tissues. They are composed of a core protein onto which glycosaminoglycan (GAG) side chains are attached via a linker region. Biallelic mutations in B3GALT6, encoding one of the linker region glycosyltransferases, are known to cause either spondyloepimetaphyseal dysplasia (SEMD) or a severe pleiotropic form of Ehlers-Danlos syndromes (EDS). This study provides clinical, molecular and biochemical data on 12 patients with biallelic B3GALT6 mutations. Notably, all patients have features of both EDS and SEMD. In addition, some patients have severe and potential life-threatening complications such as aortic dilatation and aneurysm, cervical spine instability and respiratory insufficiency. Whole-exome sequencing, next generation panel sequencing and direct sequencing identified biallelic B3GALT6 mutations in all patients. We show that these mutations reduce the amount of β3GalT6 protein and lead to a complete loss of galactosyltransferase activity. In turn, this leads to deficient GAG synthesis, and ultrastructural abnormalities in collagen fibril organization. In conclusion, this study redefines the phenotype associated with B3GALT6 mutations on the basis of clinical, molecular and biochemical data in 12 patients, and provides an in-depth assessment of β3GalT6 activity and GAG synthesis to better understand this rare condition.
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Affiliation(s)
- Tim Van Damme
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
| | - Xiaomeng Pang
- MolCelTEG Team, UMR 7365 CNRS - Université de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Brecht Guillemyn
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
| | - Sandrine Gulberti
- MolCelTEG Team, UMR 7365 CNRS - Université de Lorraine, Vandoeuvre-lès-Nancy, France
| | - Delfien Syx
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
| | - Riet De Rycke
- Department of Biomedical Molecular Biology and Expertise Centre for Transmission Electron Microscopy, Ghent University, Ghent, Belgium.,Center for Inflammation Research and BioImaging Core, VIB, Ghent, Belgium
| | - Olivier Kaye
- Centre de Rhumatologie, CHR de la Citadelle, Liège, Belgium
| | | | - Rolph Pfundt
- Department of Human Genetics, Radboud UMC, Nijmegen, Netherlands
| | | | - Sheela Nampoothiri
- Department of Pediatric Genetics, Amrita Institute of Medical Sciences & Research Centre, Cochin, Kerala, India
| | | | - Saskia Bulk
- Service de Génétique Médicale, CHU Liège, Liège, Belgium
| | - Austin A Larson
- Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital of Colorado, Aurora, CO, USA
| | - Kathryn C Chatfield
- Department of Pediatrics, University of Colorado School of Medicine and Children's Hospital of Colorado, Aurora, CO, USA
| | - Marleen Simon
- Department of Medical Genetics, University Medical Centre Utrecht, Utrecht, Netherlands
| | - Anne Legrand
- Centre de Référence des Maladies Vasculaires Rares, Hôpital Européen Georges Pompidou, Paris, France.,Paris Centre de Recherche Cardiovasculaire-PARCC, INSERM U970-Université Paris Descartes, Paris, France
| | - Marion Gerard
- Service de Génétique Clinique, Centre Hospitalier Universitaire de Caen, Caen, France
| | - Sofie Symoens
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
| | | | - Fransiska Malfait
- Center for Medical Genetics Ghent, Ghent University Hospital, Ghent, Belgium
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22
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LaCroix AJ, Stabley D, Sahraoui R, Adam MP, Mehaffey M, Kernan K, Myers CT, Fagerstrom C, Anadiotis G, Akkari YM, Robbins KM, Gripp KW, Baratela WAR, Bober MB, Duker AL, Doherty D, Dempsey JC, Miller DG, Kircher M, Bamshad MJ, Nickerson DA, Mefford HC, Sol-Church K. GGC Repeat Expansion and Exon 1 Methylation of XYLT1 Is a Common Pathogenic Variant in Baratela-Scott Syndrome. Am J Hum Genet 2019; 104:35-44. [PMID: 30554721 PMCID: PMC6323552 DOI: 10.1016/j.ajhg.2018.11.005] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 11/05/2018] [Indexed: 01/25/2023] Open
Abstract
Baratela-Scott syndrome (BSS) is a rare, autosomal-recessive disorder characterized by short stature, facial dysmorphisms, developmental delay, and skeletal dysplasia caused by pathogenic variants in XYLT1. We report clinical and molecular investigation of 10 families (12 individuals) with BSS. Standard sequencing methods identified biallelic pathogenic variants in XYLT1 in only two families. Of the remaining cohort, two probands had no variants and six probands had only a single variant, including four with a heterozygous 3.1 Mb 16p13 deletion encompassing XYLT1 and two with a heterozygous truncating variant. Bisulfite sequencing revealed aberrant hypermethylation in exon 1 of XYLT1, always in trans with the sequence variant or deletion when present; both alleles were methylated in those with no identified variant. Expression of the methylated XYLT1 allele was severely reduced in fibroblasts from two probands. Southern blot studies combined with repeat expansion analysis of genome sequence data showed that the hypermethylation is associated with expansion of a GGC repeat in the XYLT1 promoter region that is not present in the reference genome, confirming that BSS is a trinucleotide repeat expansion disorder. The hypermethylated allele accounts for 50% of disease alleles in our cohort and is not present in 130 control subjects. Our study highlights the importance of investigating non-sequence-based alterations, including epigenetic changes, to identify the missing heritability in genetic disorders.
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Affiliation(s)
- Amy J LaCroix
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA
| | - Deborah Stabley
- Nemours Biomedical Research Department, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Rebecca Sahraoui
- Nemours Biomedical Research Department, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Margaret P Adam
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA; Brotman Baty Institute for Precision Medicine, Seattle, WA 98195, USA
| | - Michele Mehaffey
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA
| | - Kelly Kernan
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA
| | | | | | | | | | - Katherine M Robbins
- Nemours Biomedical Research Department, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Karen W Gripp
- Nemours Biomedical Research Department, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Wagner A R Baratela
- Division of Orthogenetics, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; Instituto da Criança, Departamento de Pediatria, Universidade de São Paulo, São Paulo, SP Brazil
| | - Michael B Bober
- Division of Orthogenetics, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Angela L Duker
- Division of Orthogenetics, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA
| | - Dan Doherty
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA; Brotman Baty Institute for Precision Medicine, Seattle, WA 98195, USA
| | - Jennifer C Dempsey
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA
| | - Daniel G Miller
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA
| | - Martin Kircher
- Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Michael J Bamshad
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA; Brotman Baty Institute for Precision Medicine, Seattle, WA 98195, USA
| | - Deborah A Nickerson
- Brotman Baty Institute for Precision Medicine, Seattle, WA 98195, USA; Department of Genome Sciences, University of Washington, Seattle, WA 98195, USA
| | - Heather C Mefford
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA 98195, USA; Brotman Baty Institute for Precision Medicine, Seattle, WA 98195, USA.
| | - Katia Sol-Church
- Nemours Biomedical Research Department, Alfred I. duPont Hospital for Children, Wilmington, DE 19803, USA; Department of Pathology, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
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23
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Briggs DC, Hohenester E. Structural Basis for the Initiation of Glycosaminoglycan Biosynthesis by Human Xylosyltransferase 1. Structure 2018; 26:801-809.e3. [PMID: 29681470 PMCID: PMC5992326 DOI: 10.1016/j.str.2018.03.014] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 03/15/2018] [Accepted: 03/20/2018] [Indexed: 01/10/2023]
Abstract
Proteoglycans (PGs) are essential components of the animal extracellular matrix and are required for cell adhesion, migration, signaling, and immune function. PGs are composed of a core protein and long glycosaminoglycan (GAG) chains, which often specify PG function. GAG biosynthesis is initiated by peptide O-xylosyltransferases, which transfer xylose onto selected serine residues in the core proteins. We have determined crystal structures of human xylosyltransferase 1 (XT1) in complex with the sugar donor, UDP-xylose, and various acceptor peptides. The structures reveal unique active-site features that, in conjunction with functional experiments, explain the substrate specificity of XT1. A constriction within the peptide binding cleft requires the acceptor serine to be followed by glycine or alanine. The remainder of the cleft can accommodate a wide variety of sequences, but with a general preference for acidic residues. These findings provide a framework for understanding the selectivity of GAG attachment.
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Affiliation(s)
- David C Briggs
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
| | - Erhard Hohenester
- Department of Life Sciences, Imperial College London, London SW7 2AZ, UK.
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24
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Mizumoto S. Defects in Biosynthesis of Glycosaminoglycans Cause Hereditary Bone, Skin, Heart, Immune, and Neurological Disorders. TRENDS GLYCOSCI GLYC 2018. [DOI: 10.4052/tigg.1812.2j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University
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25
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Umair M, Eckstein G, Rudolph G, Strom T, Graf E, Hendig D, Hoover J, Alanay J, Meitinger T, Schmidt H, Ahmad W. Homozygous XYLT2 variants as a cause of spondyloocular syndrome. Clin Genet 2018; 93:913-918. [PMID: 29136277 DOI: 10.1111/cge.13179] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 10/27/2017] [Accepted: 10/29/2017] [Indexed: 12/20/2022]
Abstract
Spondyloocular syndrome (SOS) is a rare autosomal recessive, skeletal disorder. Two recent studies have shown that it is the result of biallelic sequence variants in the XYLT2 gene with pleiotropic effects in multiple organs, including retina, heart muscle, inner ear, cartilage, and bone. The XYLT2 gene encodes xylosyltransferase 2, which catalyzes the transfer of xylose (monosaccharide) to the core protein of proteoglycans (PGs) leading to initiating the process of PG assembly. SOS was originally characterized in 2 families A and B of Iraqi and Turkish origin, respectively. Using DNA from affected members of the same 2 families, we performed whole exome sequencing, which revealed 2 novel homozygous missense variants (c.1159C > T, p.Arg387Trp) and (c.2548G > C, p.Asp850His). Our findings extend the body of evidence that SOS is caused by homozygous variants in the XYLT2 gene. In addition, this report has extended the phenotypic description of SOS by adding follow-up data from 5 affected individuals in one of the two families, presented here.
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Affiliation(s)
- M Umair
- Institute of Human Genetics, Helmholtz Zentrum Munchen, Neuherberg, Germany
- Institute of Human Genetics, Technische Universitat, Munchen, Germany
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - G Eckstein
- Institute of Human Genetics, Helmholtz Zentrum Munchen, Neuherberg, Germany
| | - G Rudolph
- University Eye Hospital, Ludwig Maximilians University, Munich, Germany
| | - T Strom
- Institute of Human Genetics, Helmholtz Zentrum Munchen, Neuherberg, Germany
| | - E Graf
- Institute of Human Genetics, Helmholtz Zentrum Munchen, Neuherberg, Germany
| | - D Hendig
- Institute for Laboratory and Transfusion Medicine, Heart and Diabetes, Center North Rhine-Westphalia, University Hospital of the Ruhr University, Ruhr, Germany
| | - J Hoover
- University Children's Hospital, Division of Endocrinology and Diabetology, Munich, Germany
| | - J Alanay
- Institute of Human Genetics, Technische Universitat, Munchen, Germany
| | - T Meitinger
- Institute of Human Genetics, Helmholtz Zentrum Munchen, Neuherberg, Germany
- Institute of Human Genetics, Technische Universitat, Munchen, Germany
| | - H Schmidt
- University Eye Hospital, Ludwig Maximilians University, Munich, Germany
| | - W Ahmad
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
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26
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Abstract
Proteoglycans are diverse, complex extracellular/cell surface macromolecules composed of a central core protein with covalently linked glycosaminoglycan (GAG) chains; both of these components contribute to the growing list of important bio-active functions attributed to proteoglycans. Increasingly, attention has been paid to the roles of proteoglycans in nervous tissue development due to their highly regulated spatio/temporal expression patterns, whereby they promote/inhibit neurite outgrowth, participate in specification and maturation of various precursor cell types, and regulate cell behaviors like migration, axonal pathfinding, synaptogenesis and plasticity. These functions emanate from both the environments proteoglycans create around cells by retaining ions and water or serving as scaffolds for cell shaping or motility, and from dynamic interactions that modulate signaling fields for cytokines, growth factors and morphogens, which may bind to either the protein or GAG portions. Also, genetic abnormalities impacting proteoglycan synthesis during critical steps of brain development and response to environmental insults and injuries, as well as changes in microenvironment interactions leading to tumors in the central nervous system, all suggest roles for proteoglycans in behavioral and intellectual disorders and malignancies.
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Affiliation(s)
- Nancy B Schwartz
- Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA.,Department of Biochemistry and Molecular Biology, Biological Sciences Division, The University of Chicago, IL, USA
| | - Miriam S Domowicz
- Department of Pediatrics, Biological Sciences Division, The University of Chicago, IL, USA
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27
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Falardeau F, Camurri MV, Campeau PM. Genomic approaches to diagnose rare bone disorders. Bone 2017; 102:5-14. [PMID: 27474525 DOI: 10.1016/j.bone.2016.07.020] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Accepted: 07/24/2016] [Indexed: 02/01/2023]
Abstract
Skeletal dysplasias are Mendelian disorders with a prevalence of approximatively 1 in every 5000 individuals and can usually be diagnosed based on clinical and radiological findings. However, given that some diseases can be caused by several different genes, and that some genes can cause a variety of different phenotypes, achieving a molecular diagnosis can be challenging. We review here different approaches, from single gene sequencing to genomic approaches using next-generation sequencing, to reach a molecular diagnosis for skeletal dysplasias. We will further describe the overall advantages and limitations of first, second and third-generation sequencing, including single gene sequencing, whole-exome and genome sequencing (WES and WGS), multiple gene panel sequencing and single molecule sequencing. We also provide a brief overview of potential future applications of emerging technologies.
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Affiliation(s)
- Félix Falardeau
- CHU Sainte-Justine Research Center, Montreal, Canada; Division of Molecular and Cellular Biology, Department of Biology, University of Sherbrooke, Sherbrooke, Canada
| | | | - Philippe M Campeau
- CHU Sainte-Justine Research Center, Montreal, Canada; Division of Medical Genetics, Department of Pediatrics, University of Montreal, Montreal, Canada.
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28
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Al-Jezawi NK, Ali BR, Al-Gazali L. Endoplasmic reticulum retention of xylosyltransferase 1 (XYLT1) mutants underlying Desbuquois dysplasia type II. Am J Med Genet A 2017; 173:1773-1781. [PMID: 28462984 DOI: 10.1002/ajmg.a.38244] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2016] [Accepted: 03/13/2017] [Indexed: 02/05/2023]
Abstract
Desbuquois syndrome is a heterogeneous rare type of skeletal dysplasia with a prevalence of less than 1 in 1,000,000 individuals. It is characterized by short-limbed dwarfism, dysmorphic facial features, and severe joint laxity. Two types have been recognized depending on the presence of distinctive carpal and phalangeal features. Mutations in the calcium activated nucleotidase 1 (CANT1) have been found to be responsible for type I and lately, for the Kim type of Desbuquois dysplasia. In addition, a number of Desbuquois dysplasia type II patients have been attributed to mutations in xylosyltransferase 1, encoded by the XYLT1 gene, an enzyme that catalyzes the transfer of UDP-xylose (a marker of cartilage destruction) to serine residues of an acceptor protein, essential for the biosynthesis of proteoglycans. We report here a patient with features consistent with Desbuquois dysplasia II including short long bones, flat face, mild monkey wrench appearance of the femoral heads. Whole exome sequencing revealed a novel homozygous duplication of a single nucleotide in XYLT1 gene (c.2169dupA). This variant is predicted to result in a frame-shift and stop codon p.(Val724Serfs*10) within the xylosyltransferase catalytic domain. Immunoflourescence staining of HeLa cells transfected with mutated XYLT1 plasmids constructs of the current as well as the previously reported missense mutations (c.1441C>T, p.(Arg481Trp) and c.1792C>T, p.(Arg598Cys)), revealed aberrant subcellular localization of the enzyme compared to wild-type, suggesting endoplasmic reticulum retention of these mutants as the likely mechanism of disease.
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Affiliation(s)
- Nesreen K Al-Jezawi
- Department of Pathology, College of Medicine and Heath Sciences, Al-Ain, United Arab Emirates
| | - Bassam R Ali
- Department of Pathology, College of Medicine and Heath Sciences, Al-Ain, United Arab Emirates
| | - Lihadh Al-Gazali
- Department of Paediatrics, College of Medicine and Health Sciences, Al-Ain, United Arab Emirates
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29
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Guo L, Elcioglu NH, Iida A, Demirkol YK, Aras S, Matsumoto N, Nishimura G, Miyake N, Ikegawa S. Novel and recurrent XYLT1 mutations in two Turkish families with Desbuquois dysplasia, type 2. J Hum Genet 2017; 62:447-451. [PMID: 27881841 DOI: 10.1038/jhg.2016.143] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 09/30/2016] [Accepted: 10/14/2016] [Indexed: 02/03/2023]
Abstract
Desbuquois dysplasia (DBQD) is an autosomal recessive skeletal disorder characterized by growth retardation, joint laxity, short extremities, and progressive scoliosis. DBQD is classified into two types based on the presence (DBQD1) or absence (DBQD2) of characteristic hand abnormalities. CANT1 mutations have been reported in both DBQD1 and DBQD2. Recently, mutations in the gene encoding xylosyltransferase 1 (XYLT1) were identified in several families with DBQD2. In this study, we performed whole-exome sequencing in two Turkish families with DBQD2. We found a novel and a recurrent XYLT1 mutation in each family. The patients were homozygous for the mutations. Our results further support that XYLT1 is responsible for a major subset of DBQD2.
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Affiliation(s)
- Long Guo
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan
| | - Nursel H Elcioglu
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey
| | - Aritoshi Iida
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan
| | - Yasemin K Demirkol
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey
| | - Seda Aras
- Department of Pediatric Genetics, Marmara University Medical School, Istanbul, Turkey
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Gen Nishimura
- Department of Pediatric Imaging, Tokyo Metropolitan Children's Medical Center, Fuchu, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - Shiro Ikegawa
- Laboratory for Bone and Joint Diseases, RIKEN Center for Integrative Medical Sciences, Tokyo, Japan
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30
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Abstract
The zebrafish skeleton shares many similarities with human and other vertebrate skeletons. Over the past years, work in zebrafish has provided an extensive understanding of the basic developmental mechanisms and cellular pathways directing skeletal development and homeostasis. This review will focus on the cell biology of cartilage and bone and how the basic cellular processes within chondrocytes and osteocytes function to assemble the structural frame of a vertebrate body. We will discuss fundamental functions of skeletal cells in production and secretion of extracellular matrix and cellular activities leading to differentiation of progenitors to mature cells that make up the skeleton. We highlight important examples where findings in zebrafish provided direction for the search for genes causing human skeletal defects and also how zebrafish research has proven important for validating candidate human disease genes. The work we cover here illustrates utility of zebrafish in unraveling molecular mechanisms of cellular functions necessary to form and maintain a healthy skeleton.
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Affiliation(s)
- Lauryn N Luderman
- Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States; Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, United States
| | - Gokhan Unlu
- Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, United States; Vanderbilt University, Nashville, TN, United States
| | - Ela W Knapik
- Vanderbilt University Medical Center, Nashville, TN, United States; Vanderbilt Brain Institute, Vanderbilt University, Nashville, TN, United States; Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN, United States; Vanderbilt University, Nashville, TN, United States.
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31
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Job F, Mizumoto S, Smith L, Couser N, Brazil A, Saal H, Patterson M, Gibson MI, Soden S, Miller N, Thiffault I, Saunders C, Yamada S, Hoffmann K, Sugahara K, Farrow E. Functional validation of novel compound heterozygous variants in B3GAT3 resulting in severe osteopenia and fractures: expanding the disease phenotype. BMC MEDICAL GENETICS 2016; 17:86. [PMID: 27871226 PMCID: PMC5117547 DOI: 10.1186/s12881-016-0344-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 11/06/2016] [Indexed: 02/02/2023]
Abstract
Background A new disease class of syndromes, described as linkeropathies, which are derived from defects in the glycosaminoglycan-linker region as well as glycosaminoglycan-side chains of proteoglycans is increasingly being recognized as a cause of human disease. Proteoglycans are an essential component of the extracellular matrix. Defects in the enzymatic process of proteoglycan synthesis broadly occur due to the incorrect addition of side chains. Previously, homozygous missense variants within the B3GAT3 gene encoding beta 1,3 glucuronyltransferase 3(GlcAT-I) responsible for the biosynthesis of glycosaminoglycans have been described in 7 individuals. Case presentation In this study, a 4-year-old patient with a severe phenotype of osteoporosis, hypotonia, joint laxity, fractures, scoliosis, biscuspid aortic valve and myopia was referred for next generation sequencing after extensive negative clinical testing. Whole exome sequencing was performed on the proband and his unaffected parents to identify the molecular basis of his disease. Sequencing revealed compound heterozygous variants in B3GAT3: c.1A > G (p.Met1?) and c.671 T > A (p.L224Q). Clinical and in vitro functional studies were then completed to verify the pathogenicity of the genotype and further characterize the functional basis of the patient’s disease demonstrating the patient had a decrease both in the protein level of B3GAT3 and in the glucuronyltransferase activity when compared to control samples. Independent in vitro assessment of each variant confirmed the B3GAT3: c.1A > G (p.Met1?) variant is functionally null and the c.671 T > A (p.L224Q) missense variant has significantly reduced glucuronyltransferase activity (~3% of control). Conclusions This is the first report of a patient with compound heterozygosity for a null variant in trans with a missense in B3GAT3 resulting in a severe phenotype, expanding both the genotypic and phenotypic spectrum of B3GAT3-related disease. Electronic supplementary material The online version of this article (doi:10.1186/s12881-016-0344-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Florian Job
- Institute for Human Genetics and Molecular Biology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle (Saale), Germany
| | - Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi, 468-8503, Japan
| | - Laurie Smith
- University of North Carolina School of Medicine, Division of Pediatric Genetics and Metabolism, Department of Pediatrics, Raleigh, NC, USA
| | - Natario Couser
- University of North Carolina School of Medicine, Division of Pediatric Genetics and Metabolism, Department of Pediatrics, Raleigh, NC, USA
| | - Ashley Brazil
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Howard Saal
- Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Melanie Patterson
- Department of Pathology, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Margaret I Gibson
- Department of Pathology, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Sarah Soden
- Department of Pediatrics, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Neil Miller
- Department of Medical Informatics, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Isabelle Thiffault
- Department of Pathology, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Carol Saunders
- Department of Pathology, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA
| | - Shuhei Yamada
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi, 468-8503, Japan
| | - Katrin Hoffmann
- Institute for Human Genetics and Molecular Biology, Martin Luther University Halle-Wittenberg, Magdeburger Str. 2, 06112, Halle (Saale), Germany
| | - Kazuyuki Sugahara
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, 150 Yagotoyama, Tempaku-ku, Nagoya, Aichi, 468-8503, Japan. .,The Laboratory of Proteoglycan Signaling and Therapeutics, Graduate School of Life Science, Faculty of Advanced Life Science, Hokkaido University, Sapporo, 001-0021, Japan.
| | - Emily Farrow
- Department of Pediatrics, Children's Mercy Hospitals and Clinics, Kansas City, MO, USA. .,Center for Pediatric Genomic Medicine, Children's Mercy Hospitals and Clinics, 2420 Pershing, Suite 100, Kansas City, MO, USA.
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Silveira C, Leal GF, Cavalcanti DP. Desbuquois dysplasia type II in a patient with a homozygous mutation in XYLT1 and new unusual findings. Am J Med Genet A 2016; 170:3043-3047. [PMID: 27481334 DOI: 10.1002/ajmg.a.37858] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Accepted: 07/01/2016] [Indexed: 01/02/2023]
Affiliation(s)
- Cynthia Silveira
- Skeletal Dysplasia Group, Department of Medical Genetic, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Gabriela F Leal
- Professor Fernando Figueira Integral Medicine Institute (IMIP), Recife, Pernambuco, Brazil
| | - Denise P Cavalcanti
- Skeletal Dysplasia Group, Department of Medical Genetic, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
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Vodopiutz J, Mizumoto S, Lausch E, Rossi A, Unger S, Janocha N, Costantini R, Seidl R, Greber-Platzer S, Yamada S, Müller T, Jilma B, Ganger R, Superti-Furga A, Ikegawa S, Sugahara K, Janecke AR. Chondroitin SulfateN-acetylgalactosaminyltransferase-1 (CSGalNAcT-1) Deficiency Results in a Mild Skeletal Dysplasia and Joint Laxity. Hum Mutat 2016; 38:34-38. [DOI: 10.1002/humu.23070] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2016] [Accepted: 08/29/2016] [Indexed: 11/11/2022]
Affiliation(s)
- Julia Vodopiutz
- Department of Pediatrics and Adolescent Medicine; Medical University of Vienna; Vienna Austria
| | - Shuji Mizumoto
- Department of Pathobiochemistry; Faculty of Pharmacy; Meijo University; Tempaku ku; Nagoya Aichi Japan
| | - Ekkehart Lausch
- Department of Pediatrics; Medical Center, Faculty of Medicine; University of Freiburg; Freiburg Germany
| | - Antonio Rossi
- Department of Molecular Medicine; Unit of Biochemistry; University of Pavia; Pavia Italy
| | - Sheila Unger
- Department of Medical Genetics; Centre Hospitalier Universitaire Vaudois; University of Lausanne; Lausanne Switzerland
| | - Nikolaus Janocha
- Department of Pediatrics; Medical Center, Faculty of Medicine; University of Freiburg; Freiburg Germany
| | - Rossella Costantini
- Department of Molecular Medicine; Unit of Biochemistry; University of Pavia; Pavia Italy
| | - Rainer Seidl
- Department of Pediatrics and Adolescent Medicine; Medical University of Vienna; Vienna Austria
| | - Susanne Greber-Platzer
- Department of Pediatrics and Adolescent Medicine; Medical University of Vienna; Vienna Austria
| | - Shuhei Yamada
- Department of Pathobiochemistry; Faculty of Pharmacy; Meijo University; Tempaku ku; Nagoya Aichi Japan
| | - Thomas Müller
- Department of Pediatrics I; Medical University of Innsbruck; Innsbruck Austria
| | - Bernd Jilma
- Department of Clinical Pharmacology; Medical University of Vienna; Vienna Austria
| | - Rudolf Ganger
- Paediatric Department; Orthopaedic Hospital of Speising; Vienna Austria
| | - Andrea Superti-Furga
- Department of Pediatrics; Centre Hospitalier Universitaire Vaudois; University of Lausanne; Lausanne Switzerland
| | - Shiro Ikegawa
- Laboratory for Bone and Joint Diseases; Center for Integrative Medical Sciences; RIKEN; Tokyo Japan
| | - Kazuyuki Sugahara
- Department of Pathobiochemistry; Faculty of Pharmacy; Meijo University; Tempaku ku; Nagoya Aichi Japan
| | - Andreas R. Janecke
- Department of Pediatrics I; Medical University of Innsbruck; Innsbruck Austria
- Division of Human Genetics; Medical University of Innsbruck; Innsbruck Austria
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Taylan F, Costantini A, Coles N, Pekkinen M, Héon E, Şıklar Z, Berberoğlu M, Kämpe A, Kıykım E, Grigelioniene G, Tüysüz B, Mäkitie O. Spondyloocular Syndrome: Novel Mutations in XYLT2 Gene and Expansion of the Phenotypic Spectrum. J Bone Miner Res 2016; 31:1577-85. [PMID: 26987875 DOI: 10.1002/jbmr.2834] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2016] [Revised: 03/06/2016] [Accepted: 03/10/2016] [Indexed: 01/08/2023]
Abstract
Spondyloocular syndrome is an autosomal-recessive disorder with spinal compression fractures, osteoporosis, and cataract. Mutations in XYLT2, encoding isoform of xylosyltransferase, were recently identified as the cause of the syndrome. We report on 4 patients, 2 unrelated patients and 2 siblings, with spondyloocular syndrome and novel mutations in XYLT2. Exome sequencing revealed a homozygous nonsense mutation, NM_022167.3(XYLT2): c.2188C>T, resulting in a premature stop codon (p.Arg730*) in a female patient. The patient presents visual impairment, generalized osteoporosis, short stature with short trunk, spinal compression fractures, and increased intervertebral disc space and hearing loss. We extended our XYLT2 analysis to a cohort of 22 patients with generalized osteoporosis, mostly from consanguineous families. In this cohort, we found by Sanger sequencing 2 siblings and 1 single patient who were homozygous for missense mutations in the XYLT2 gene (p.Arg563Gly and p.Leu605Pro). The patients had osteoporosis, compression fractures, cataracts, and hearing loss. Bisphosphonate treatment in 1 patient resulted in almost complete normalization of vertebral structures by adolescence, whereas treatment response in the others was variable. This report together with a previous study shows that mutations in the XYLT2 gene result in a variable phenotype dominated by spinal osteoporosis, cataract, and hearing loss. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Fulya Taylan
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Alice Costantini
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Nicole Coles
- Department of Pediatric Endocrinology of Metabolism, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | | | - Elise Héon
- Department of Pediatric Endocrinology of Metabolism, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Zeynep Şıklar
- Department of Pediatric Endocrinology, School of Medicine, Ankara University, Ankara, Turkey
| | - Merih Berberoğlu
- Department of Pediatric Endocrinology, School of Medicine, Ankara University, Ankara, Turkey
| | - Anders Kämpe
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Ertuğrul Kıykım
- Department of Pediatric Metabolism, Cerrahpasa Medicine School, Istanbul University, Istanbul, Turkey
| | - Giedre Grigelioniene
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Beyhan Tüysüz
- Department of Pediatric Genetics, Cerrahpasa Medicine School, Istanbul University, Istanbul, Turkey
| | - Outi Mäkitie
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden
- Folkhälsan Institute of Genetics, Helsinki, Finland
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
- Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
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35
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Jamsheer A, Olech EM, Kozłowski K, Niedziela M, Sowińska-Seidler A, Obara-Moszyńska M, Latos-Bieleńska A, Karczewski M, Zemojtel T. Exome sequencing reveals two novel compound heterozygous XYLT1 mutations in a Polish patient with Desbuquois dysplasia type 2 and growth hormone deficiency. J Hum Genet 2016; 61:577-83. [PMID: 27030147 DOI: 10.1038/jhg.2016.30] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2015] [Revised: 02/27/2016] [Accepted: 03/08/2016] [Indexed: 01/09/2023]
Abstract
Desbuquois dysplasia type 2 (DBQD2) is a rare recessively inherited skeletal genetic disorder characterized by severe prenatal and postnatal growth retardation, generalized joint laxity with dislocation of large joints and facial dysmorphism. The condition was recently described to result from autosomal recessive mutations in XYLT1, encoding the enzyme xylosyltransferase-1. In this paper, we report on a Polish patient with DBQD2 who presented with severe short stature of prenatal onset, joint laxity, psychomotor retardation and multiple radiological abnormalities including short metacarpals, advanced bone age and exaggerated trochanters. Endocrinological examinations revealed that sleep-induced growth hormone (GH) release and GH peak in clonidine- and glucagon-induced provocative tests as well as insulin-like growth factor 1 (IGF-1) and IGF-binding protein-3 levels were all markedly decreased, confirming deficiency of GH secretion. Bone age, unlikely to GH deficiency, was significantly advanced. To establish the diagnosis at a molecular level, we performed whole-exome sequencing and bioinformatic analysis in the index patient, which revealed compound heterozygous XYLT1 mutations: c.595C>T(p.Gln199*) and c.1651C>T(p.Arg551Cys), both of which are novel. Sanger sequencing showed that the former mutation was inherited from the healthy mother, whereas the latter one most probably occurred de novo. Our study describes the first case of DBQD2 resulting from compound heterozygous XYLT1 mutation, expands the mutational spectrum of the disease and provides evidence that the severe growth retardation and microsomia observed in DBQD2 patients may result not only from the skeletal dysplasia itself but also from GH and IGF-1 deficiency.
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Affiliation(s)
- Aleksander Jamsheer
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
- NZOZ Center for Medical Genetics GENESIS, Poznan, Poland
| | - Ewelina M Olech
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - Kazimierz Kozłowski
- Department of Medical Imaging, The Children's Hospital at Westmead, Sydney, NSW, Australia
| | - Marek Niedziela
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, Poznan, Poland
- Karol Jonscher's Clinical Hospital, Poznan University of Medical Sciences, Poznan, Poland
| | - Anna Sowińska-Seidler
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - Monika Obara-Moszyńska
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, Poznan, Poland
- Karol Jonscher's Clinical Hospital, Poznan University of Medical Sciences, Poznan, Poland
| | - Anna Latos-Bieleńska
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
- NZOZ Center for Medical Genetics GENESIS, Poznan, Poland
| | - Marek Karczewski
- Department of Transplantology, General, Vascular and Plastic Surgery Clinical Hospital of Poznan University of Medical Sciences, Poznan, Poland
| | - Tomasz Zemojtel
- Institute for Medical Genetics and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany
- Institute of Bioorganic Chemistry, Polish Academy of Sciences, Poznan, Poland
- Labor Berlin-Charité Vivantes GmbH, Humangenetik, Berlin, Germany
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36
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Arunrut T, Sabbadini M, Jain M, Machol K, Scaglia F, Slavotinek A. Corneal clouding, cataract, and colobomas with a novel missense mutation in B4GALT7-a review of eye anomalies in the linkeropathy syndromes. Am J Med Genet A 2016; 170:2711-8. [PMID: 27320698 DOI: 10.1002/ajmg.a.37809] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 06/06/2016] [Indexed: 12/18/2022]
Abstract
We present a 5-year-old female with a distinctive phenotype comprising global developmental delays, pre- and post-natal growth restriction, striking joint laxity with soft skin, and scoliosis. She had a triangular facies, a prominent forehead, proptosis, a small nose, and a small jaw. Her ocular findings included corneal clouding, colobomas of the iris and optic nerve, and posterior subcapsular cataracts. Exome sequencing identified homozygosity for c.970T>A, predicting p.(Cys324Ser), in the xylosylprotein 4-beta-galactosyltransferase, polypeptide 7 (B4GALT7) gene. Variant segregation was consistent with autosomal recessive inheritance and the missense substitution was predicted to be pathogenic. As the phenotype of this child is consistent with that described in other "linkeropathy" syndromes, we conclude that p.(Cys324Ser) is likely to be disease-causing. The eye features were a notable part of this child's presentation and mutations in the linkeropathy genes (XYLT1, XYLT2, B4GALT7, B3GALT6, and B3GAT3) can be associated with ocular findings, including blue sclerae, refractive errors, corneal clouding, strabismus, nystagmus, cataracts, glaucoma, and retinal abnormalities, including retinal detachment. The corneal clouding and cataracts in this patient may thus have been caused by her B4GALT7 mutation, but the colobomas are a novel phenotypic finding. However, a different genetic etiology or a role for modifying genetic factors has not been excluded in the etiology of her colobomas. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Teda Arunrut
- Division of Genetics, Department of Pediatrics, University of California, San Francisco, California
| | - Marta Sabbadini
- Division of Genetics, Department of Pediatrics, University of California, San Francisco, California
| | - Mahim Jain
- Department of Medical Genetics, Baylor College of Medicine, Houston, Texas
| | - Keren Machol
- Department of Medical Genetics, Baylor College of Medicine, Houston, Texas
| | - Fernando Scaglia
- Department of Medical Genetics, Baylor College of Medicine, Houston, Texas
| | - Anne Slavotinek
- Division of Genetics, Department of Pediatrics, University of California, San Francisco, California.
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van Koningsbruggen S, Knoester H, Bakx R, Mook O, Knegt L, Cobben JM. Complete and partial XYLT1 deletion in a patient with neonatal short limb skeletal dysplasia. Am J Med Genet A 2016; 170A:510-514. [PMID: 26601923 DOI: 10.1002/ajmg.a.37453] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 10/21/2015] [Indexed: 11/07/2022]
Abstract
We report on a boy with a neonatal short limb skeletal dysplasia with serious medical complications, associated with one intragenic and one complete deletion of XYLT1. XYLT1 mutations have recently been reported as causative in recessive Desbuquois skeletal dysplasia (DBSD), but the skeletal features in our patient do not fit this diagnosis. It is possible that the phenotype of XYLT1 mutations extends to more aspecific types of short limb skeletal dysplasias and not to DBSD alone.
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Affiliation(s)
| | - Hennie Knoester
- Department of Pediatric Intensive Care Medicine, Emma Childrens Hospital, AMC University Hospital, Amsterdam, The Netherlands
| | - Roel Bakx
- Department of Pediatric Surgery, Pediatric Surgical Center, Amsterdam, The Netherlands
| | - Olaf Mook
- Department of Medical Genetics, AMC University Hospital, Amsterdam, The Netherlands
| | - Lia Knegt
- Department of Medical Genetics, AMC University Hospital, Amsterdam, The Netherlands
| | - Jan Maarten Cobben
- Department of Pediatric Genetics, AMC University Hospital, Amsterdam, The Netherlands
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38
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Mutations in Biosynthetic Enzymes for the Protein Linker Region of Chondroitin/Dermatan/Heparan Sulfate Cause Skeletal and Skin Dysplasias. BIOMED RESEARCH INTERNATIONAL 2015; 2015:861752. [PMID: 26582078 PMCID: PMC4637088 DOI: 10.1155/2015/861752] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 07/05/2015] [Indexed: 01/11/2023]
Abstract
Glycosaminoglycans, including chondroitin, dermatan, and heparan sulfate, have various roles in a wide range of biological events such as cell signaling, cell proliferation, tissue morphogenesis, and interactions with various growth factors. Their polysaccharides covalently attach to the serine residues on specific core proteins through the common linker region tetrasaccharide, -xylose-galactose-galactose-glucuronic acid, which is produced through the stepwise addition of respective monosaccharides by four distinct glycosyltransferases. Mutations in the human genes encoding the glycosyltransferases responsible for the biosynthesis of the linker region tetrasaccharide cause a number of genetic disorders, called glycosaminoglycan linkeropathies, including Desbuquois dysplasia type 2, spondyloepimetaphyseal dysplasia, Ehlers-Danlos syndrome, and Larsen syndrome. This review focused on recent studies on genetic diseases caused by defects in the biosynthesis of the common linker region tetrasaccharide.
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39
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News on Clinical Details and Treatment in PGM1-CDG. JIMD Rep 2015; 26:77-84. [PMID: 26303607 PMCID: PMC5580736 DOI: 10.1007/8904_2015_471] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Revised: 05/29/2015] [Accepted: 06/05/2015] [Indexed: 01/28/2023] Open
Abstract
Phosphoglucomutase 1 deficiency has recently been reported as a novel disease that belongs to two different classes of metabolic disorders, congenital disorders of glycosylation (CDG) and glycogen storage diseases.This paper focuses on previously reported siblings with short stature, hypothyroidism, increased transaminases, and, in one of them, dilated cardiomyopathy (DCM). An intronic point mutation in the PGM1-gene (c.1145-222 G>T) leads to a complex alternative splicing pattern and to almost complete absence of PGM1 activity.Exercise-induced muscle fatigue, chest pain, and rhabdomyolysis persisted into adulthood. Fainting occurred during the first minutes of strong exercise due to glucose depletion and serum heart troponin was increased. A second wind phenomenon with an improvement in exercise capacity after some minutes of training was observed. Regular aerobic training improved fitness and helped to avoid acute damage. DCM improved during therapy.Glycosylation deficiency was most prominent in childhood. Glycosylation improved with age and further improved with oral galactose supplementation even in adulthood. Optimal improvement of glycosylation-dependent phenotypes should be achieved by early and permanent galactose treatment.However, in case of mutations in ZASP, DCM can develop as a consequence of impaired binding of PGM1 to the heart-specific isoform of ZASP, independently of overall glycosylation efficiency. Thus, even if mutations in PGM1 impair the function of the ZASP-PGM1 complex, supplementation of galactose cannot be expected to restore that function. Therefore, knowledge of PGM1 deficiency in a patient should prompt surveillance of early signs of DCM and specific treatment if necessary.
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Jones KL, Schwarze U, Adam MP, Byers PH, Mefford HC. A homozygous B3GAT3 mutation causes a severe syndrome with multiple fractures, expanding the phenotype of linkeropathy syndromes. Am J Med Genet A 2015; 167A:2691-6. [PMID: 26086840 DOI: 10.1002/ajmg.a.37209] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Accepted: 06/03/2015] [Indexed: 11/12/2022]
Abstract
Linkeropathies are a group of syndromes characterized by short stature, radio-ulnar synostosis, decreased bone density, congenital contractures and dislocations, joint laxity, broad digits, brachycephaly, small mouth, prominent eyes, short or webbed neck, congenital heart defects and mild developmental delay. Linkeropathies are due to enzymatic defects in the synthesis of the common linker region that joins the core proteins to their glycosaminoglycan (GAG) side chains. The enzyme glucuronyltransferase 1, encoded by B3GAT3, adds the last four saccharides comprising the linker region. Mutations in B3GAT3 have been reported in two unrelated families with the same homozygous mutation (c.830G>A, p.Arg277Gln). We report on a patient with a novel homozygous B3GAT3 (c.667G>A, p.Gly223Ser) mutation and a history of multiple fractures, blue sclerae, and glaucoma. Our patient was a 12-month-old boy born to consanguineous parents and, like previously reported patients, he had bilateral radio-ulnar synostosis, severe osteopenia, an increased gap between first and second toes, bilateral club feet, and atrial and ventricular septal defects. He had the additional features of bilateral glaucoma, hypertelorism, upturned nose with anteverted nares, a small chest, a diaphragmatic hernia, multiple fractures, arachnodactyly, overlapping fingers with ulnar deviation, lymphedema, hypotonia, hearing loss, and perinatal cerebral infarction with bilateral supra- and infratentorial subdural hematomas. We highlight the extended phenotypic range of B3GAT3 mutations and a provide comparative overview of the phenotypic features of the linkeropathies associated with mutations in XYLT1, B4GALT7, B3GALT6, and B3GAT3.
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Affiliation(s)
- Kelly L Jones
- Division of Genetic Medicine, Department of Pediatrics, University of Washington & Seattle Children's Hospital, Seattle, Washington
| | - Ulrike Schwarze
- Department of Pathology, University of Washington, Seattle, Washington
| | - Margaret P Adam
- Division of Genetic Medicine, Department of Pediatrics, University of Washington & Seattle Children's Hospital, Seattle, Washington
| | - Peter H Byers
- Department of Pathology, University of Washington, Seattle, Washington.,Department of Medicine, University of Washington, Seattle, Washington
| | - Heather C Mefford
- Division of Genetic Medicine, Department of Pediatrics, University of Washington & Seattle Children's Hospital, Seattle, Washington
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41
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Munns CF, Fahiminiya S, Poudel N, Munteanu MC, Majewski J, Sillence DO, Metcalf JP, Biggin A, Glorieux F, Fassier F, Rauch F, Hinsdale ME. Homozygosity for frameshift mutations in XYLT2 result in a spondylo-ocular syndrome with bone fragility, cataracts, and hearing defects. Am J Hum Genet 2015; 96:971-8. [PMID: 26027496 PMCID: PMC4457947 DOI: 10.1016/j.ajhg.2015.04.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 04/24/2015] [Indexed: 01/05/2023] Open
Abstract
Heparan and chondroitin/dermatan sulfated proteoglycans have a wide range of roles in cellular and tissue homeostasis including growth factor function, morphogen gradient formation, and co-receptor activity. Proteoglycan assembly initiates with a xylose monosaccharide covalently attached by either xylosyltransferase I or II. Three individuals from two families were found that exhibited similar phenotypes. The index case subjects were two brothers, individuals 1 and 2, who presented with osteoporosis, cataracts, sensorineural hearing loss, and mild learning defects. Whole exome sequence analyses showed that both individuals had a homozygous c.692dup mutation (GenBank: NM_022167.3) in the xylosyltransferase II locus (XYLT2) (MIM: 608125), causing reduced XYLT2 mRNA and low circulating xylosyltransferase (XylT) activity. In an unrelated boy (individual 3) from the second family, we noted low serum XylT activity. Sanger sequencing of XYLT2 in this individual revealed a c.520del mutation in exon 2 that resulted in a frameshift and premature stop codon (p.Ala174Profs(∗)35). Fibroblasts from individuals 1 and 2 showed a range of defects including reduced XylT activity, GAG incorporation of (35)SO4, and heparan sulfate proteoglycan assembly. These studies demonstrate that human XylT2 deficiency results in vertebral compression fractures, sensorineural hearing loss, eye defects, and heart defects, a phenotype that is similar to the autosomal-recessive disorder spondylo-ocular syndrome of unknown cause. This phenotype is different from what has been reported in individuals with other linker enzyme deficiencies. These studies illustrate that the cells of the lens, retina, heart muscle, inner ear, and bone are dependent on XylT2 for proteoglycan assembly in humans.
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Affiliation(s)
- Craig F Munns
- Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia
| | - Somayyeh Fahiminiya
- Department of Human Genetics, Faculty of Medicine, McGill University and Genome Quebec Innovation Center, Montréal, QC H3A 1B1, Canada
| | - Nabin Poudel
- Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, USA
| | | | - Jacek Majewski
- Department of Human Genetics, Faculty of Medicine, McGill University and Genome Quebec Innovation Center, Montréal, QC H3A 1B1, Canada
| | - David O Sillence
- Discipline of Genetic Medicine, The Children's Hospital at Westmead Clinical School, Sydney Medicine, Westmead, NSW 2145, Australia
| | - Jordan P Metcalf
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA
| | - Andrew Biggin
- Institute of Endocrinology and Diabetes, The Children's Hospital at Westmead, Westmead, NSW 2145, Australia
| | | | | | - Frank Rauch
- Shriners Hospital for Children, Montréal, QC H3G 1A6, Canada
| | - Myron E Hinsdale
- Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078, USA; Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73126, USA.
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Abstract
Skeletal dysplasias result from disruptions in normal skeletal growth and development and are a major contributor to severe short stature. They occur in approximately 1/5,000 births, and some are lethal. Since the most recent publication of the Nosology and Classification of Genetic Skeletal Disorders, genetic causes of 56 skeletal disorders have been uncovered. This remarkable rate of discovery is largely due to the expanded use of high-throughput genomic technologies. In this review, we discuss these recent discoveries and our understanding of the molecular mechanisms behind these skeletal dysplasia phenotypes. We also cover potential therapies, unusual genetic mechanisms, and novel skeletal syndromes both with and without known genetic causes. The acceleration of skeletal dysplasia genetics is truly spectacular, and these advances hold great promise for diagnostics, risk prediction, and therapeutic design.
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43
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Budde BS, Mizumoto S, Kogawa R, Becker C, Altmüller J, Thiele H, Rüschendorf F, Toliat MR, Kaleschke G, Hämmerle JM, Höhne W, Sugahara K, Nürnberg P, Kennerknecht I. Skeletal dysplasia in a consanguineous clan from the island of Nias/Indonesia is caused by a novel mutation in B3GAT3. Hum Genet 2015; 134:691-704. [PMID: 25893793 DOI: 10.1007/s00439-015-1549-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 03/30/2015] [Indexed: 12/31/2022]
Abstract
We describe a large family with disproportionate short stature and bone dysplasia from Nias in which we observed differences in severity when comparing the phenotypes of affected individuals from two remote branches. We conducted a linkage scan in the more severely affected family branch and determined a critical interval of 4.7 cM on chromosome 11. Sequencing of the primary candidate gene TBX10 did not reveal a disease-causing variant. When performing whole exome sequencing we noticed a homozygous missense variant in B3GAT3, c.419C>T [p.(Pro140Leu)]. B3GAT3 encodes β-1,3-glucuronyltransferase-I (GlcAT-I). GlcAT-I catalyzes an initial step of proteoglycan synthesis and the mutation p. (Pro140Leu) lies within the donor substrate-binding subdomain of the catalytic domain. In contrast to the previously published mutation in B3GAT3, c.830G>A [p.(Arg277Gln)], no heart phenotype could be detected in our family. Functional studies revealed a markedly reduced GlcAT-I activity in lymphoblastoid cells from patients when compared to matched controls. Moreover, relative numbers of glycosaminoglycan (GAG) side chains were decreased in patient cells. We found that Pro140Leu-mutant GlcAT-I cannot efficiently transfer GlcA to the linker region trisaccharide. This failure results in a partial deficiency of both chondroitin sulfate and heparan sulfate chains. Since the phenotype of the Nias patients differs from the Larsen-like syndrome described for patients with mutation p.(Arg277Gln), we suggest mutation B3GAT3:p.(Pro140Leu) to cause a different type of GAG linkeropathy showing no involvement of the heart.
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Affiliation(s)
- Birgit S Budde
- Cologne Center for Genomics (CCG), University of Cologne, Cologne, Germany
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Kuhn J, Götting C, Beahm BJ, Bertozzi CR, Faust I, Kuzaj P, Knabbe C, Hendig D. Xylosyltransferase II is the predominant isoenzyme which is responsible for the steady-state level of xylosyltransferase activity in human serum. Biochem Biophys Res Commun 2015; 459:469-74. [PMID: 25748573 PMCID: PMC6598695 DOI: 10.1016/j.bbrc.2015.02.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Accepted: 02/22/2015] [Indexed: 01/13/2023]
Abstract
In mammals, two active xylosyltransferase isoenzymes (EC 2.4.2.16) exist. Both xylosyltransferases I and II (XT-I and XT-II) catalyze the transfer of xylose from UDP-xylose to select serine residues in the proteoglycan core protein. Altered XT activity in human serum was found to correlate directly with various diseases such as osteoarthritis, systemic sclerosis, liver fibrosis, and pseudoxanthoma elasticum. To interpret the significance of the enzyme activity alteration observed in disease states it is important to know which isoenzyme is responsible for the XT activity in serum. Until now it was impossible for a specific measurement of XT-I or XT-II activity, respectively, because of the absence of a suitable enzyme substrate. This issue has now been solved and the following experimental study demonstrates for the first time, via the enzyme activity that XT-II is the predominant isoenzyme responsible for XT activity in human serum. The proof was performed using natural UDP-xylose as the xylose donor, as well as the artificial compound UDP-4-azido-4-deoxyxylose, which is a selective xylose donor for XT-I.
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Affiliation(s)
- Joachim Kuhn
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany.
| | - Christian Götting
- MVZ Labor Limbach Nürnberg, Lina-Ammon-Strasse 28, 90471 Nürnberg, Germany
| | - Brendan J Beahm
- Department of Chemistry and Molecular and Cell Biology Howard Hughes Medical Institute University of California, Berkeley, CA 94720, USA
| | - Carolyn R Bertozzi
- Department of Chemistry and Molecular and Cell Biology Howard Hughes Medical Institute University of California, Berkeley, CA 94720, USA
| | - Isabel Faust
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany
| | - Patricia Kuzaj
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany
| | - Doris Hendig
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Georgstraße 11, 32545 Bad Oeynhausen, Germany
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Maeda N. Proteoglycans and neuronal migration in the cerebral cortex during development and disease. Front Neurosci 2015; 9:98. [PMID: 25852466 PMCID: PMC4369650 DOI: 10.3389/fnins.2015.00098] [Citation(s) in RCA: 114] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 03/07/2015] [Indexed: 12/13/2022] Open
Abstract
Chondroitin sulfate proteoglycans and heparan sulfate proteoglycans are major constituents of the extracellular matrix and the cell surface in the brain. Proteoglycans bind with many proteins including growth factors, chemokines, axon guidance molecules, and cell adhesion molecules through both the glycosaminoglycan and the core protein portions. The functions of proteoglycans are flexibly regulated due to the structural variability of glycosaminoglycans, which are generated by multiple glycosaminoglycan synthesis and modifying enzymes. Neuronal cell surface proteoglycans such as PTPζ, neuroglycan C and syndecan-3 function as direct receptors for heparin-binding growth factors that induce neuronal migration. The lectican family, secreted chondroitin sulfate proteoglycans, forms large aggregates with hyaluronic acid and tenascins, in which many signaling molecules and enzymes including matrix proteases are preserved. In the developing cerebrum, secreted chondroitin sulfate proteoglycans such as neurocan, versican and phosphacan are richly expressed in the areas that are strategically important for neuronal migration such as the striatum, marginal zone, subplate and subventricular zone in the neocortex. These proteoglycans may anchor various attractive and/or repulsive cues, regulating the migration routes of inhibitory neurons. Recent studies demonstrated that the genes encoding proteoglycan core proteins and glycosaminoglycan synthesis and modifying enzymes are associated with various psychiatric and intellectual disorders, which may be related to the defects of neuronal migration.
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Affiliation(s)
- Nobuaki Maeda
- Neural Network Project, Department of Brain Development and Neural Regeneration, Tokyo Metropolitan Institute of Medical Science Setagaya, Japan
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Faust I, Böker KO, Eirich C, Akkermann D, Kuhn J, Knabbe C, Hendig D. Identification and characterization of human xylosyltransferase II promoter single nucleotide variants. Biochem Biophys Res Commun 2015; 458:901-7. [PMID: 25704086 DOI: 10.1016/j.bbrc.2015.02.056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 02/11/2015] [Indexed: 10/24/2022]
Abstract
The human isoenzymes xylosyltransferase-I and -II (XT-I, XT-II) catalyze the rate-limiting step in proteoglycan biosynthesis. Therefore, serum XT activity, mainly representing XT-II activity, displays a powerful biomarker to quantify the actual proteoglycan synthesis rate. Serum XT activity is increased up to 44% in disorders which are characterized by an altered proteoglycan metabolism, whereby underlying regulatory mechanisms remain unclear. The aim of this study was to investigate new regulatory pathways by identifying and characterizing naturally occurring XYLT2 promoter sequence variants as well as their potential influence on promoter activity and serum XT activity. XYLT2 promoter single nucleotide variants (SNVs) were identified and genotyped in the genomic DNA of 100 healthy blood donors by promoter amplification and sequencing or restriction fragment length polymorphism analysis. The SNVs were characterized by an in silico analysis considering genetic linkage and transcription factor binding sites (TBSs). The influence of SNVs on promoter activity and serum XT activity was determined by dual luciferase reporter assay and HPLC-ESI mass spectrometry. Allele frequencies of seven XYLT2 promoter sequence variants identified were investigated. In silico analyses revealed a strong genetic linkage of SNVs c.-80delG and c.-188G > A, c.-80delG and c.-1443G > A, as well as c.-188G > A and c.-1443G > A. However, despite the generation of several SNV-associated changes in TBSs in silico, XYLT2 promoter SNVs did not significantly affect promoter activity. Serum XT activities of SNV carriers deviated up to 8% from the wild-type, whereby the differences were also not statistically significant. This is the first study which identifies, genotypes and characterizes XYLT2 promoter SNVs. Our results reveal a weak genetic heterogeneity and a strong conservation of the human XYLT2 promoter region. Since the SNVs detected could be excluded as causatives for strong interindividual variabilities in serum XT activity, our data provide increasing evidence that XT-II activity is obviously regulated by hitherto unknown complex genetic pathways, such as cis- or trans-acting enhancers, silencers or miRNAs.
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Affiliation(s)
- Isabel Faust
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Kai Oliver Böker
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Christina Eirich
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Dagmar Akkermann
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Joachim Kuhn
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Doris Hendig
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
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Faust I, Böker KO, Lichtenberg C, Kuhn J, Knabbe C, Hendig D. First description of the complete human xylosyltransferase-I promoter region. BMC Genet 2014; 15:129. [PMID: 25480529 PMCID: PMC4264549 DOI: 10.1186/s12863-014-0129-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 11/17/2014] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Human xylosyltransferase-I (XT-I) catalyzes the rate-limiting step in proteoglycan glycosylation. An increase in XYLT1 mRNA expression and serum XT activity is associated with diseases characterized by abnormal extracellular matrix accumulation like, for instance, fibrosis. Nevertheless, physiological and pathological mechanisms of transcriptional XT regulation remain elusive. RESULTS To elucidate whether promoter variations might affect the naturally occurring variability in serum XT activity, a complete sequence analysis of the XYLT1 promoter was performed in genomic DNA of healthy blood donors. Based on promoter amplification by a specialized PCR technique, sequence analysis revealed a fragment of 238 bp, termed XYLT1 238*, which has never been described in the human XYLT1 reference sequence so far. In silico characterization of this unconsidered fragment depicted an evolutionary conservation between sequences of Homo sapiens and Pan troglodytes (chimpanzee) or Mus musculus (mouse), respectively. Promoter activity studies indicated that XYLT1 238* harbors various transcription factor binding sites affecting basal XYLT1 expression and inducibility by transforming growth factor-β1, the key fibrotic mediator. A microsatellite and two single nucleotide variants (SNV), c.-403C>T and c.-1088C>A, were identified and genotyped in 100 healthy blood donors. Construct associated changes in XYLT1 promoter activity were detected for several sequence variants, whereas serum XT activity was only marginally affected. CONCLUSIONS Our findings describe for the first time the entire XYLT1 promoter sequence and provide new insights into transcriptional regulation of XT-I. Future studies should analyze the impact of regulatory XYLT1 promoter variations on XT-associated diseases.
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Affiliation(s)
- Isabel Faust
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Kai Oliver Böker
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Christoph Lichtenberg
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Joachim Kuhn
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Cornelius Knabbe
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
| | - Doris Hendig
- Institut für Laboratoriums- und Transfusionsmedizin, Herz- und Diabeteszentrum Nordrhein-Westfalen, Universitätsklinik der Ruhr-Universität Bochum, Bad Oeynhausen, Germany.
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Ritelli M, Chiarelli N, Zoppi N, Dordoni C, Quinzani S, Traversa M, Venturini M, Calzavara-Pinton P, Colombi M. Insights in the etiopathology of galactosyltransferase II (GalT-II) deficiency from transcriptome-wide expression profiling of skin fibroblasts of two sisters with compound heterozygosity for two novel B3GALT6 mutations. Mol Genet Metab Rep 2014. [PMID: 28649518 PMCID: PMC5471164 DOI: 10.1016/j.ymgmr.2014.11.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Mutations in B3GALT6, encoding the galactosyltransferase II (GalT-II) involved in the synthesis of the glycosaminoglycan (GAG) linkage region of proteoglycans (PGs), have recently been associated with a spectrum of connective tissue disorders, including spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMDJL1) and Ehlers–Danlos-like syndrome. Here, we report on two sisters compound heterozygous for two novel B3GALT6 mutations that presented with severe short stature and progressive kyphoscoliosis, joint hypermobility and laxity, hyperextensible skin, platyspondyly, short ilia, and elbow malalignment. Microarray-based transcriptome analysis revealed the differential expression of several genes encoding extracellular matrix (ECM) structural components, including COMP, SPP1, COL5A1, and COL15A1, enzymes involved in GAG synthesis and in ECM remodeling, such as CSGALNACT1, CHPF, LOXL3, and STEAP4, signaling transduction molecules of the TGFβ/BMP pathway, i.e., GDF6, GDF15, and BMPER, and transcription factors of the HOX and LIM families implicated in skeletal and limb development. Immunofluorescence analyses confirmed the down-regulated expression of some of these genes, in particular of the cartilage oligomeric matrix protein and osteopontin, encoded by COMP and SPP1, respectively, and showed the predominant reduction and disassembly of the heparan sulfate specific GAGs, as well as of the PG perlecan and type III and V collagens. The key role of GalT-II in GAG synthesis and the crucial biological functions of PGs are consistent with the perturbation of many physiological functions that are critical for the correct architecture and homeostasis of various connective tissues, including skin, bone, cartilage, tendons, and ligaments, and generates the wide phenotypic spectrum of GalT-II-deficient patients. Clinical features/molecular characterization of two patients with spondyloepimetaphyseal dysplasia with joint laxity type 1 Identification of two novel B3GALT6 mutations First report of transcriptome-wide gene expression profiling on GalT-II-deficient fibroblasts Immunofluorescence studies of several ECM structural components in GalT-II-deficient cells Enlargement of the knowledge on the GalT-II deficiency’s molecular pathogenesis
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Key Words
- ATCS, adducted-thumb club foot syndrome
- Abs, antibodies
- B3GALT6
- BMP, bone morphogenetic proteins
- C4ST, chondroitin 4-sulfotransferase
- C6ST, chondroitin 6-sulfotransferase
- COLLI, type I collagen
- COLLIII, type III collagen
- COLLV, type V collagen
- COLLs, collagens
- COMP, cartilage oligomeric matrix protein
- CS, chondroitin sulfate
- CSGALNACT1, chondroitin sulfate N-acetylgalactosaminyltransferase 1
- CTDs, connective tissue disorders
- Cartilage oligomeric matrix protein
- ChPF, chondroitin polymerizing factor
- ChSy, chondroitin synthase
- D4ST, dermatan 4 sulfotransferase 1
- DCN, decorin
- DEGs, differentially expressed genes
- DS, dermatan sulfate
- ECM, extracellular matrix
- EDS, Ehlers–Danlos syndrome
- Ehlers–Danlos syndrome
- FN, fibronectin
- GAGs, glycosaminoglycans
- GO, gene ontology
- Gal, galactose
- GalNAc, N-acetylgalactosamine
- GalNAc4S-6ST, GalNAc 4-sulfate 6-O-sulfotransferase
- GalNAcT, β1,4-N-acetylgalactosaminyltransferase
- GalNAcT-16, N-acetylgalactosaminyltransferase 16
- GalT-I/II, galactosyltransferase I and II
- GalT-II deficiency
- GlcA, glucuronic acid
- GlcAT, glucuronosyltransferase
- GlcNAc, N-acetylglucosamine
- GlcNAcT, α1,4-N-acetylglucosaminyltransferase
- HA, hyaluronic acid
- HAS2, hyaluronan synthase 2
- HOX, homeobox gene family
- HPO, human phenotype ontology
- HS, heparan sulfate
- Hep, heparin
- IF, immunofluorescence microscopy studies
- IdoA, iduronic acid
- OPN, osteopontin
- Osteopontin
- PGs, proteoglycans
- PTC, premature termination codon of translation
- SEMDJL1, spondyloepimetaphyseal dysplasia with joint laxity type 1
- Spondyloepimetaphyseal dysplasia with joint laxity type 1
- TNs, tenascins
- Xyl, xylose
- XylT, xylosyltransferase
- qPCR, quantitative polymerase chain reaction
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Affiliation(s)
- Marco Ritelli
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Nicola Chiarelli
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Nicoletta Zoppi
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Chiara Dordoni
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Stefano Quinzani
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Michele Traversa
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
| | - Marina Venturini
- Division of Dermatology, Department of Clinical and Experimental Sciences, Spedali Civili University Hospital, Brescia, Italy
| | - Piergiacomo Calzavara-Pinton
- Division of Dermatology, Department of Clinical and Experimental Sciences, Spedali Civili University Hospital, Brescia, Italy
| | - Marina Colombi
- Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Brescia, Italy
- Corresponding author at: Division of Biology and Genetics, Department of Molecular and Translational Medicine, School of Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
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Xylose phosphorylation functions as a molecular switch to regulate proteoglycan biosynthesis. Proc Natl Acad Sci U S A 2014; 111:15723-8. [PMID: 25331875 DOI: 10.1073/pnas.1417993111] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Most eukaryotic cells elaborate several proteoglycans critical for transmitting biochemical signals into and between cells. However, the regulation of proteoglycan biosynthesis is not completely understood. We show that the atypical secretory kinase family with sequence similarity 20, member B (Fam20B) phosphorylates the initiating xylose residue in the proteoglycan tetrasaccharide linkage region, and that this event functions as a molecular switch to regulate subsequent glycosaminoglycan assembly. Proteoglycans from FAM20B knockout cells contain a truncated tetrasaccharide linkage region consisting of a disaccharide capped with sialic acid (Siaα2-3Galβ1-4Xylβ1) that cannot be further elongated. We also show that the activity of galactosyl transferase II (GalT-II, B3GalT6), a key enzyme in the biosynthesis of the tetrasaccharide linkage region, is dramatically increased by Fam20B-dependent xylose phosphorylation. Inactivating mutations in the GALT-II gene (B3GALT6) associated with Ehlers-Danlos syndrome cause proteoglycan maturation defects similar to FAM20B deletion. Collectively, our findings suggest that GalT-II function is impaired by loss of Fam20B-dependent xylose phosphorylation and reveal a previously unappreciated mechanism for regulation of proteoglycan biosynthesis.
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